PS3 Frankenstein PHAT PS3: CECHA with 40nm RSX

[truemaster]

ps2 functionality is something im interested too i have a cok-001 motherbord full of 3034 errors that is waiting the mod

 

[RIP-Felix]

Hello friends, well I've heard from DeathEnd, I just found out there's a problem with the PS2, unfortunately I haven't been able to try it (because of isolation), when the shop opens (August 9th) I'll look for the problem. So far, no one (Indonesian) has talked about the PS2, so I just found out.
Little explanation:
One of the advantages of the cok-001 and cok-002 motherboards is that there is additional PS2 hardware embedded in the motherboard, with such conditions you can say that PS2 & PS3 each work independently, what distinguishes cok-001 from cok-002 is the AV output line, cok -002 there is no problem on the ps2 because the AV output line is directly from the ps2 hardware itself (as far as I remember), while for cok-001 the ps2 hardware AV output line is on the RSX AV line, so when we replace the RSX, there may be something wrong with it. The AV output line, could also be due to interference from the AV output of the RSX itself, as you have experienced.
In the past, there was also a problem with the installation of the cok-001, where after replacing the RSX, the PS3 (GLOD) output image did not come out, after exploring, we finally found the solution by adding 47K
see picture.
View attachment 34429
View attachment 34430
I'm sorry for not paying attention to PS2 (cok-001), I'll find the cause later, tq

What would happen if I put a 10k resistor back on R2153? Not the one I used to pull CGreset high, another one from a donor board? From looking at the schematic that's RS_TRSTNEG, a JTAG signal to Mullion (SYSCON chip). Removing R2153 leaves the signal floating (no path to GND).

Quite a while back I wrote a post wondering about this...

Okay this is going over my head, so someone familiar with JTAG needs to chime in. I found this JTAG PowerPC controller information with the keywords "TRSTNEG." It says, the signal TRSTNEG is the... SONY labeled the signal "RS_RSTSNEG". I'm not sure if the RS stands for "Reality Synthesizer" or "Reset Signal," but I'm leaning toward the latter. R2153 has to do with setting the JTAG signal state. The "NEG" might refer to placing the compliance setting in "Negation." This document says, If I understand this right, removing R2153 cuts power to RS_TRSTNEG. I think that means Reset Signal to the PowerPC PPE in the CELL BE. What I can't figure out is what that means. Is it outputting a reset signal until the SYSCON sends a reset signal to synchronize the startup of both processors? Or by cutting power to it, are we circumventing the SYSCON control and essentially hacking it to start immediately? IDK, but this sound like the right path forward. It's above my experience level, so please chime in if you're familiar with JTAG reset signals, especially for PowerPC's.

Like I said it's like the PS2 is being held in reset. It's the same behavior on a SNES when the lockout chip doesn't receive the correct signal from the security chip on the cartridge, it holds reset down until it receives the correct signal to release it and start the game. That "feels" exactly like what's happening with the PS2. The on screen display can still be accessed and I can exit back to the menu just fine. The PS3 and emulated PS1 environment is unaffected. It's just the coordination between the system and PS2 HW that seems to be broken.

I wonder if reset can't be triggered, which perhaps it needs to be in order to synchronize the PS2 HW. Until then, the PS2 is held in reset...forever in this case. I am, of course talking strait out my butt and have no idea if any of this makes sense. It's a good sounding combination of words that my feeble mind is attempting to make patterns out of. So take it with a grain of salt.

 

[Pacorretaco]

ps2 functionality is something im interested too i have a cok-001 motherbord full of 3034 errors that is waiting the mod

Yes, after all ps2 functionality might as well be what makes all these threads exist in the first place.

What would happen if I put a 10k resistor back on R2153? Not the one I used to pull CGreset high, another one from a donor board? From looking at the schematic that's RS_TRSTNEG, a JTAG signal to Mullion (SYSCON chip). Removing R2153 leaves the signal floating (no path to GND).

Quite a while back I wrote a post wondering about this...


Like I said it's like the PS2 is being held in reset. It's the same behavior on a SNES when the lockout chip doesn't receive the correct signal from the security chip on the cartridge, it holds reset down until it receives the correct signal to release it and start the game. That "feels" exactly like what's happening with the PS2. The on screen display can still be accessed and I can exit back to the menu just fine. The PS3 and emulated PS1 environment is unaffected. It's just the coordination between the system and PS2 HW that seems to be broken.

I wonder if reset can't be triggered, which perhaps it needs to be in order to synchronize the PS2 HW. Until then, the PS2 is held in reset...forever in this case. I am, of course talking strait out my butt and have no idea if any of this makes sense. It's a good sounding combination of words that my feeble mind is attempting to make patterns out of. So take it with a grain of salt.

Well try it!

It takes a COK 001 board with a modchip, and a high curiosity to find out. Which is exactly what you have hehehe.

It might just work, who knows. If not, I think it's something that should still be in our realm of possibility because after all this was done officially too. And nuking ps2 hardware is not something they'd be happy with.
We know that 40nm is possible even on COK 001 while keeping ps2 HW functional. So if there is some incompatibility it should be circumventable.

@DoublesAdvocate maybe consider getting ready that official 40nm COK 001 for more in-depth comparisons?

But, I think it's still not even fair to settle on any conclusions so he can wait.
Botakompong (welcome back) says he didn't hear anything about ps2 working or not working. That doesn't mean anything. Normally not hearing anything means it's all OK hehe.

In my opinion the first thing would still be doing it on another board and see what happens. After all Felix's board was "one" unknown board where RSX was swapped first and asked questions later. So not really enough to conclude anything I'd say.

In any case we can be hopeful I think.

 

[vyktormvmpay25]

I'm curious about that but really didn't find any. Tried to find here bought one more" with 4 USB ports " (that's what seller told) with " sticker seal untouched" and board well cooked and heated on barbeque, and 1 kg of thermal paste on both. It's hard to get it here.
Nobody wants to tell model number or what repair attempts are done. At least from last I assume they did " towel reflow" outside case is melted.
3 ohms cpu /1.8 ohms rsx, didn't even bother to read errors.

 

[RIP-Felix]

Yes, after all ps2 functionality might as well be what makes all these threads exist in the first place.

Well try it!

It takes a COK 001 board with a modchip, and a high curiosity to find out. Which is exactly what you have hehehe.

It might just work, who knows. If not, I think it's something that should still be in our realm of possibility because after all this was done officially too. And nuking ps2 hardware is not something they'd be happy with.
We know that 40nm is possible even on COK 001 while keeping ps2 HW functional. So if there is some incompatibility it should be circumventable.

I want confirmation it's not going to interfere or destroy the modchip first! I only have the one. Moreover the console works now, it just doesn't play PS2 games. While that completly defeats the purpose, it's still useful to have for testing purposes (thermal tests, for example). So I'm hesitant to do a bunch of trial and error testing that "might" cause damage. I doubt it will, probably just YLOD with an error that will be easily removed by undoing the change, but I don't want to chance it.

Thank you for bringing up @DoublesAdvocate console! Had you not I wouldn't have found the following. I was just going to ask if we know for sure offical COK-001 refirbs ever played PS2 games? You were referring to this post, but if you recall, his COK-001 refirb was freezing in PS2 games! I mean, his at least loads! That's when I noticed a small detail that kind blows my mind and raises a lot of questions about whether or not SONY even got this to work on COK-001 consoles at all.

If you skip to 9:07 he can still access the on screen display, just like my console! How do I know my console isn't freezing in PS2 games too? It never loads, which made me think it doesn't start at all. But who knows if that's a different issue or not? It could just be a spectrum of symptoms with the same root cause. His is frozen at a point where something was on screen. Mine does it before anything has displayed yet. Maybe my issue is just worse than his, occuring immediatly on PS2 boot instead of a few minutes in.

We can't rule out the possibility that it's the same issue. Also, it may or may not be related to the mod. We could just have the same PS2 hardware failure. IDK.

@DoublesAdvocate are you still around? Would you be willing to do some testing for posterity? Hi-REz pictures of the motherboard would be much appreciated! Especially closeups of the modded areas. We know they used a different MOSFET driver that allow the VCC output to be selected by external resistors via pads nearby (the stock one is set using internal resistors). However, we only have grainy pictures of this. And we don't have measurements! That would be useful for comparison because there could be other resistor values changed to reduce the VCC of other RSX input voltages. @DeadEnd just informed me that on What's App @botakompong just posted 2 pictures of other resistor mods to COK-001 boards using his mod chip!!! This is news to us! He has not previously mentioned these mods.

Spoiler: Extra resistor mods for COK-001 w/mod chip)

It's possible there may be other, less obvious changes we're not aware of. If Sony also removed resistors and replaced them with different values we would probably miss that kind of change. Unless we know where to probe and measure, we'd be in the dark. Unless there were a clear color difference, or something visually different, we'd just "assume" it's stock.

All the users that have an official refirb have stopped posting. The Original Post didn't show any PS2 footage or state it worked. I assume he would have told us if it didn't work or froze. However, assuming is not good practice. I want confirmation! Unless I'm forgetting some post where PS2 functionality was proven to work flawlessly, there's a remote possibility the 40nm RSX never worked properly with PS2 games.

 

[DoublesAdvocate]

@Pacorretaco @RIP-Felix Yup I'm still here and I've still got my official 40nm refurb. I think the issue that it has with the PS2 games is similar to the issue that I've seen on units without any refurb history. Basically when I try to boot up PS2 games and the console is still cold it will often freeze after only a few seconds, I can still quit to the XMB again mind you but no matter how many times I try to launch the PS2 game it always locks up at around the same point. If you try to play PS2 games after letting it warm up a bit it works just fine though, and I've noticed this exact same issue and behaviour on regular DECHA and CECHA/B consoles with the original 90nm RSX so I suspect it's an issue with the PS2 circuitry and is completely unrelated to the 40nm refurb process or the changing of the syscon.

 

[Pacorretaco]

All the users that have an official refirb have stopped posting. The Original Post didn't show any PS2 footage or state it worked. I assume he would have told us if it didn't work or froze. However, assuming is not good practice. I want confirmation! Unless I'm forgetting some post where PS2 functionality was proven to work flawlessly, there's a remote possibility the 40nm RSX never worked properly with PS2 games.

Ahh, no I don't think it's the same problem. His 40nm COK 001 is working fine in ps2 mode.
This is just a reminder of how these machines really are. Random freezes are to be expected.
To me it's just astounding that they even work at all. The level of complexity and room for failure is incredibly high.
Could even be the southbridge for all we know...
After having both I'd say that there are instances where the partial emulation COK 002 models work better than the 001.

We call the 001 "full hardware" ps2 support but it's also not nearly full at all. Many things are still emulated in weird ways which are not even the same as the newer models... Network support comes to mind.

Anyway I got sidetracked a bit but the point is that these great machines are incredibly complex.
Random freezes and issues are expected. Also the userbase was always so small that we don't even know that much what to expect in the first place. Some things aren't even tested really.

 

[RIP-Felix]

@Pacorretaco @RIP-Felix Yup I'm still here and I've still got my official 40nm refurb. I think the issue that it has with the PS2 games is similar to the issue that I've seen on units without any refurb history. Basically when I try to boot up PS2 games and the console is still cold it will often freeze after only a few seconds, I can still quit to the XMB again mind you but no matter how many times I try to launch the PS2 game it always locks up at around the same point. If you try to play PS2 games after letting it warm up a bit it works just fine though, and I've noticed this exact same issue and behaviour on regular DECHA and CECHA/B consoles with the original 90nm RSX so I suspect it's an issue with the PS2 circuitry and is completely unrelated to the 40nm refurb process or the changing of the syscon.

Hmm...if it's responding to heat, then I would normally think BGA. Perhaps the rework popped a BGA on the EE+GS?

I certainly do not want it to have anything to do with the frankenstein mod. Either official or modchip. If it's PS2 HW related then there's a chance I can still fix it. So I hope you're right. Have you ever fixed a console that had this issue? Has anyone?

 

[Pacorretaco]

@Pacorretaco @RIP-Felix Yup I'm still here and I've still got my official 40nm refurb. I think the issue that it has with the PS2 games is similar to the issue that I've seen on units without any refurb history. Basically when I try to boot up PS2 games and the console is still cold it will often freeze after only a few seconds, I can still quit to the XMB again mind you but no matter how many times I try to launch the PS2 game it always locks up at around the same point. If you try to play PS2 games after letting it warm up a bit it works just fine though, and I've noticed this exact same issue and behaviour on regular DECHA and CECHA/B consoles with the original 90nm RSX so I suspect it's an issue with the PS2 circuitry and is completely unrelated to the 40nm refurb process or the changing of the syscon.

Hmm...if it's responding to heat, then I would normally think BGA. Perhaps the rework popped a BGA on the EE+GS?

I certainly do not want it to have anything to do with the frankenstein mod. Either official or modchip. If it's PS2 HW related then there's a chance I can still fix it. So I hope you're right. Have you ever fixed a console that had this issue? Has anyone?

Hmm wait no. I was talking about expected normal operation. I don't think this can even be considered a hardware issue that can be fixed at all.

I'd really do another board before breaking my head trying to figure out the "problem" which may not even exist.
Maybe you could have some lost cause board dead without RSX anyway, and could borrow the modchip from the board that has it but is a mistery?

 

[Pacorretaco]

@Pacorretaco @RIP-Felix Yup I'm still here and I've still got my official 40nm refurb. I think the issue that it has with the PS2 games is similar to the issue that I've seen on units without any refurb history. Basically when I try to boot up PS2 games and the console is still cold it will often freeze after only a few seconds, I can still quit to the XMB again mind you but no matter how many times I try to launch the PS2 game it always locks up at around the same point. If you try to play PS2 games after letting it warm up a bit it works just fine though, and I've noticed this exact same issue and behaviour on regular DECHA and CECHA/B consoles with the original 90nm RSX so I suspect it's an issue with the PS2 circuitry and is completely unrelated to the 40nm refurb process or the changing of the syscon.

Oh I posted before seeing your post.
Do the freezes tend to happen more in cutscenes / intense data loading?
Have you tried different games?
In my experience the highest chance to crash it is wirh long cutscenes or things like that. Skipping them makes the thing more reliable.

So I suspect it's an I/O thing
I mean it could even be something like a weak optical laser

 

[RIP-Felix]

@Pacorretaco we're not talking about a random PS2 freeze that occurs infrequently. Watch the video he posed and I embedded in my post above. You can see it just freezes after a couple of minutes into the game's opening. Perhaps that could be chalked up to buggy "normal operation" if it were a one off thing. But he's talking about it happening repeatedly. I've never experienced any issues with PS2 functionality in my other COK-001 consoles. No random freezes, nothing like his. Certainly not like the issue I'm having.

 

[Pacorretaco]

@Pacorretaco we're not talking about a random PS2 freeze that occurs infrequently. Watch the video he posed and I embedded in my post above. You can see it just freezes after a couple of minutes into the game's opening. Perhaps that could be chalked up to buggy "normal operation" if it were a one off thing. But he's talking about it happening repeatedly. I've never experienced any issues with PS2 functionality in my other COK-001 consoles. No random freezes, nothing like his. Certainly not like the issue I'm having.

Sure, because I don't think it has anything to do with the black screen issue you are having.

For your other consoles, If you want I might ask you to test some specific things to try and replicate what I'm saying. I've actually been curious about this stuff for a while. But I don't think my COK 001 board has a hardware fault either.
Problems that don't happen in 002 boards

But maybe we are getting sidetracked here

 

[marciolsf]

As it turns out, my cecha01 is a refurb, I think. It died of ylod one day fairly early in its lifetime... I want to say it was around 2009. The circumstances were odd too -- I was playing one late afternoon, then turned it off. I turned it back on about 2 mins later to check on something, then turned it off. I then accidentally bumped the home button and bam! Ylod. I contacted Sony and sent it back for repairs, and about a month later I had it back. It worked fine until it died again late 2019 (in much the same way - power off, then power one a few mins later to be greeted by a ylod). It also played ps2 games just fine.

I guess the long story short is -- why did Sony started doing the mod? My bet is that they were low on supply, so it would have to have been some time into the slims lifetime. @DoublesAdvocate, did you acquire your moded ps3 from a 3rd party? Or was it your own refurb?

 

[DeadEnd]

@RIP-Felix Please try this mod and report if anything changes. I think the problem was that we have misunderstood the instructions for cok-001.

Basically remove R2001 and R2002 (they are not 47k, it appears they are 49.9 ohms) and add a 47k in place of R2002.

 

[DoublesAdvocate]

@RIP-Felix I sincerely doubt it's a BGA issue on the PS2 chip since those EE+GS chips run extremely cool and have a soldered IHS, other than a manufacturing defect I think the chances of it getting a BGA failure from thermal cycling are almost 0. Given the strange behaviour it exhibits in relation to temperature I'm leaning more to it being some resistor or capacitor that's simply worn out it's welcome and needs replacing, which one it might be though I have no idea.

@marciolsf This one was purchased from a 3rd party used but is 100% an official refurb as it shows the rare syscon version.

 

[RIP-Felix]

@RIP-Felix Please try this mod and report if anything changes. I think the problem was that we have misunderstood the instructions for cok-001.

Basically remove R2001 and R2002 (they are not 47k, it appears they are 49.9 ohms) and add 47k in place of R2002.

View attachment 34448
View attachment 34449

I was wondering to myself (somewhat miffed by your nonchalant 'just replace with a 47K resistor' comment), "yeah, and where exactly might I find a 47kΩ resistor?" Easy to say, but it turned out to be hard to find!

I had been staring at the COK-001 schematic for half an hour and haden't found one. I do have a scrap KTE-001 board, but besides it I only have COK-001 donors to harvest body parts from. So instead of searching the PDF, I decided it would be faster to just probe for 47K resistors. An hour later I had probed EVERY resistor on the KTE-001 board and found 1 here...

That's the only one I was able to find. 47K is aparently an uncommon valuey. There were lots of 10K, by comparison! I didn't probe every resistor on the COK-001, but most of them before I went cross-eyed and gave up!

So I have 1, and only 1, 47k resistor that I was able to find. If I don't loose it when removing it, which is easy to do, maybe I can attempt this today. I hope I don't have to buy them from mouser! Otherwise it'll have to wait.

So the question now is, do I need to replace both R2002 and R2001, or just R2002? He say's discard both and replace with 47k, but then shows a picture of the mod tutorial where only R2002 is populated and R2001 is not.

This likely makes a difference, because COK-001 R2002 and R2001 are a voltage divider to GS_CLKI. I guessing that stands for Grapshics Synthesizer Clock Input. Seems promising either way.

Resistor voltage dividers are commonly used to create reference voltages, or to reduce the magnitude of a voltage so it can be measured, and may also be used as signal attenuators at low frequencies...

• Vin = 1.5v_RSX_RC_VDDA.
• R1 = R2001 (Stock = 49.9)
  
• R2 = R2002 (Stock = 49.9)
  
• Vout = RSX Pin AM39 (GS_CLKI)

Vout = 49.9 / (49.9+49.9) X 1.5v
Vout = 0.75v, it divides the voltage by 2 if both values are the same.

This gives us 3 possible scenarios:

1. Replace R2001 & R2002 w/47K. The resulting voltage is the same. Vout = 0.75v (stock). However, it changes is the attenuation of the low pass RC filter (R2001 & C2001). The stock 49.9 ohm R2001 results in a crossover frequency of 32KHz. Any frequency higher than that will effectively be filtered. Replacing it with a 47K resistor changes that frequency to 34Hz! That's 34 hertz not kilohertz! That's a big change. If there were any important signals that need to pass between 34Hz-32KHz, they will be blocked by this change in the LP filter! However, I don't think that's the point of this RC filter. I'm "guessing" this filter is to decoupled noise from the GS. The PS2's GS clock frequency is ~147MHz, so that would definitely be blocked by both filters. IDK for sure if that's the clock frequency GSCLKI is referring to, but if it is, then at best this mod would be pointless.
   
2. Replace R2002 w/47K and Vout = 1.498V! Nearly equal to 1.5v_RSX_RC_VDDA. Twice the stock voltage.
   
3. Replace R2001 w/47K and Vout = 0.0169v. Almost zero.

Now, I don't want to go doubling the input voltage on a pin to the RSX without knowing what effect that will have. For all I know, it could fry an important circuit! It would be safer to try lowering it, but again IDK what effect that might have.

It's may be relevent to note that these circuits are different between COK-001 and COK-002 boards. On a COK-002 board the voltage divider resistors are unpopulated and there is instead an incoming signal (RSX_GSCLKI) being sent to pin AM39 (GSCLKI)...

The COK-002 only has a Graphics Syntesizer (GS) and most of the other functions are emulated by Cell SPEs.

On a COK-001 the voltage divider resistors are present, because there exists actual PS2 hardware. There is no incoming RSX_GSCLKI signal...

I'm wondering if the EE+GS and it's PS2 bridge controller cordinate the GSCLKI and are connected to the RSX reset circuit via some other line. On a COK-002 the Graphics Synthesizer (IC8001) has RSX_GSCLKOUT1-G on pin Y32. RSX_GSCLKOUT1 has a resistor labeled R8027, who's trace I followed and then very carefully counted the DAMN vias to confirm it is RSX_GSCLKI! So yes, the GS sends that signal directly to the RSX in COK-002 boards.

Populating R2002 with a 47K resistor then would have what effect?Does it pull voltage High? In effect saying, "yeah I'm on." I'm struggling with that part. Also, COK-001 boards are more complicated and my brain hurts from staring at the schematics. If "feel" like I'm onto something, but have worn myself out trying to put together the above. So I'll pick it back up later.

Here's where we are. I still need to figure out what effect populating R2002 has in COK-002. What's the point? We know it's what the mod requires, but why? And I still need to figure out what effect doing the same would have on a COK-001.

Maybe some of this makes sense to someone out there, but for now I'm fried!

 

[vyktormvmpay25]

Felix on Sem001 pdf there are values of resistors, think 47 k could be on power button pcb not sure didn't check. I got mine from Sem001 from exactly that area after power button ic.

 

[Pacorretaco]

I was wondering to myself (somewhat miffed by your nonchalant 'just replace with a 47K resistor' comment), "yeah, and where exactly might I find a 47kΩ resistor?" Easy to say, but it turned out to be hard to find!

I had been staring at the COK-001 schematic for half an hour and haden't found one. I do have a scrap KTE-001 board, but besides it I only have COK-001 donors to harvest body parts from. So instead of searching the PDF, I decided it would be faster to just probe for 47K resistors. An hour later I had probed EVERY resistor on the KTE-001 board and found 1 here...
View attachment 34452

That's the only one I was able to find. 47K is aparently an uncommon valuey. There were lots of 10K, by comparison! I didn't probe every resistor on the COK-001, but most of them before I went cross-eyed and gave up!

So I have 1, and only 1, 47k resistor that I was able to find. If I don't loose it when removing it, which is easy to do, maybe I can attempt this today. I hope I don't have to buy them from mouser! Otherwise it'll have to wait.

So the question now is, do I need to replace both R2002 and R2001, or just R2002? He say's discard both and replace with 47k, but then shows a picture of the mod tutorial where only R2002 is populated and R2001 is not.

This likely makes a difference, because COK-001 R2002 and R2001 are a voltage divider to GS_CLKI. I guessing that stands for Grapshics Synthesizer Clock Input. Seems promising either way.

• Vin = 1.5v_RSX_RC_VDDA.
• R1 = R2001 (Stock = 49.9)
  
• R2 = R2002 (Stock = 49.9)
  
• Vout = RSX Pin AM39 (GS_CLKI)

Vout = 49.9 / (49.9+49.9) X 1.5v
Vout = 0.75v, it divides the voltage by 2 if both values are the same.

This gives us 3 possible scenarios:

1. Replace R2001 & R2002 w/47K. The resulting voltage is the same. Vout = 0.75v (stock). However, it changes is the attenuation of the low pass RC filter (R2001 & C2001). The stock 49.9 ohm R2001 results in a crossover frequency of 32KHz. Any frequency higher than that will effectively be filtered. Replacing it with a 47K resistor changes that frequency to 34Hz! That's 34 hertz not kilohertz! That's a big change. If there were any important signals that need to pass between 34Hz-32KHz, they will be blocked by this change in the LP filter! However, I don't think that's the point of this RC filter. I'm "guessing" this filter is to decoupled noise from the GS. The PS2's GS clock frequency is ~147MHz, so that would definitely be blocked by both filters. IDK for sure if that's the clock frequency GSCLKI is referring to, but if it is, then at best this mod would be pointless.
   
2. Replace R2002 w/47K and Vout = 1.498V! Nearly equal to 1.5v_RSX_RC_VDDA. Twice the stock voltage.
   
3. Replace R2001 w/47K and Vout = 0.0169v. Almost zero.

Now, I don't want to go doubling the input voltage on a pin to the RSX without knowing what effect that will have. For all I know, it could fry an important circuit! It would be safer to try lowering it, but again IDK what effect that might have.

It's may be relevent to note that these circuits are different between COK-001 and COK-002 boards. On a COK-002 board the voltage divider resistors are unpopulated and there is instead an incoming signal (RSX_GSCLKI) being sent to pin AM39 (GSCLKI)...View attachment 34453
The COK-002 only has a Graphics Syntesizer (GS) and most of the other functions are emulated by Cell SPEs.

On a COK-001 the voltage divider resistors are present, because there exists actual PS2 hardware. There is no incoming RSX_GSCLKI signal...View attachment 34454

I'm wondering if the EE+GS and it's PS2 bridge controller cordinate the GSCLKI and are connected to the RSX reset circuit via some other line. On a COK-002 the Graphics Synthesizer (IC8001) has RSX_GSCLKOUT1-G on pin Y32. RSX_GSCLKOUT1 has a resistor labeled R8027, who's trace I followed and then very carefully counted the DAMN vias to confirm it is RSX_GSCLKI! So yes, the GS sends that signal directly to the RSX in COK-002 boards.

Populating R2002 with a 47K resistor then would have what effect?Does it pull voltage High? In effect saying, "yeah I'm on." I'm struggling with that part. Also, COK-001 boards are more complicated and my brain hurts from staring at the schematics. If "feel" like I'm onto something, but have worn myself out trying to put together the above. So I'll pick it back up later.

Here's where we are. I still need to figure out what effect populating R2002 has in COK-002. What's the point? We know it's what the mod requires, but why? And I still need to figure out what effect doing the same would have on a COK-001.

Maybe some of this makes sense to someone out there, but for now I'm fried!

R6016 for example should be a 47k resistor in COK boards

 

[RIP-Felix]

Good eyes Paco! THX.

I spy with my little eye, something different that no-one else did!

Remember this post?

Hi
My English is not very good so use google translation
Share the PS3 purchased by my friend
(Replace PS3 with 40nm RSX)

I hope everyone can understand

I own a cecha00 (Made in China) because of the YLOD problem, so I need to replace the TOKIN/NEC capacitor.
I think it is the problem of TOKIN/NEC capacitors, and now I want to buy the capacitors.
After I get it, I have to replace my PS3.

However, because of fear of RSX also having problems.
So I also bought the re-balled RSX to replace it.

In addition, is there a way to make a simple measurement to determine whether RSX is good or is there a problem?

A few days ago, my friend bought a cecha00 (Made in Japan)
When disassembling to replace the thermal paste, he found that RSX is 40nm (CXD5300A1GB)
He informed me about this problem
I also took pictures to show me
His cecha00 motherboard is COK-001 just like mine

I saw the picture
RSX was replaced with a 40nm package
I also found that there are other differences besides the 45-degree resistance

Then I found this discussion on this forum
So also provide the photos he gave me for reference

The model of cecha00 is also very precious
Hope to find out the correct way to replace 40nm RSX
After all, 40nm has less heat than 90nm


Attached below is a photo of my friend's PS3 motherboard

Well he posted the best pictures of an official sony refirb that we have. You have the power to change this @DoublesAdvocate! Anyway...

That means SONY removed R2001 and replaced R2002 with a black resistor. Guess what color the 47K resistor is? BLACK! We were all laser focused in on the diagonal resistor (R2054) and the removal of R2153. We never noticed R2001 was gone and R2002 was different! And @botakompong's instructions have a confusing translation that let my primitive ape brain be lazy! I didn't want to have to do more microsoldering of flea turds, so I accepted the first explanation that allowed me to believe I didn't have to! And yet that picture has been there all this time just waiting for us to notice the correct way to do it!

This is the mod that refuses to be understood! At least we now know there is another HW change needed for the Official method. @squeept may want to look into that, since it could explain why his results didn't work. The mod chip allows my console to boot. Perhaps, the official method doesn't!

 

[RIP-Felix]

Okay, I just replaced R2002 with that resistor I measured (in circuit) was 47K and I removed R2001. Nothing changed at all. No YLOD or any change in behavior. It still plays PS1/3 games, but fails to load PS2. Dang, I was hoping that was it.

On the other hand, after replacing it, it reads 33K (in circuit) now. So I'm wondering if it's actually a 47K resistor after all I didn't think to read it while I had it off the board). I know reading resistance in circuit is frowned upon, but in truth I forgot. There wouldn't be any question had I used R6016 like Paco suggested.

I'm just hoping to get @botakompong's opinion before I try again. That greainy picture is hard to tell if R2001 is actually unpopulated or not. I don't see any blue, or the outline of a resistor, but it's not definitive. @DoublesAdvocate could you take a picture of your board? You don't have to separate the HS from the MB, if that bothers you. I just did all the above soldering without separating them! Just remove the leaf springs and lift up the RF shielding to get the picture. A resistance measurement of the diangonal resistor, R2002, and R2001 (if it's there) would get you bonus points!