PS3 Frankenstein PHAT PS3: CECHA with 40nm RSX

Something went wrong on gddr? Not sure, may have to do further research
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I know you don't like the edit the eeprom, but would you make an exception so we can see the "lasterrlog"?

Here's an oscilloscope image of the startup sequence for comparison:
1x probes, DC coupled, 20MHz BW limit, and High res acquisition mode enabled (CPU yellow, GPU = Blue):
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After the startup sequence, if everything is good, the RSX begins a regular 60Hz signal...
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The length of the YLOD event gives a clue as to how far into the POST process the console is getting. It shouldn't take longer than 350ms if everything is good. When everything is normal, the CPU (yellow line in the examples above) will drop onto the last voltage plateau. Shortly after that (within a second or two) the RSX will begin a 60Hz signal (sync maybe? NTSC video? IDK exactly, just know it's 60Hz). In my experiance a 40 3034 will cause it to stall on the second to last voltage plateau. The CPU voltage never drops to the last plateau and the YLOD occurs some time after that (can be seconds later). If it stalls on the second to last plateau, then it's having a hard time in the bit training phase of POST and the "lasterrlog" will show the specific bittraining error code...
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In the example above (needed a reball) the bittraining error RSX:RRAC:BX0:BX:FLEXIO_ID gives us more information to go on. I think that tells us specifically where the connection was lost, but someone more experience with the actual pinouts will want to chime in there. So @squeept, if you can get internal command access, then the lasterrlog might provide critical information.
 
Moving it back to normal gets rid of the 2120. Still gets 3034 and 4001 at once.
That shouldn't have worked if you removed the pull-up resistor R2153. Can you post a picture of the hardware changes you made? Can you confirm these are the hardware changes you made in the first test?
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If you grounded the CGreset (R2054), but forgot to remove RS_TRSTNEG (R2153), the error would go away after putting R2054 back the way it was. Maybe that's why the 2120 error cleared? If you forgot to do this, let's try again.

However, if you had removed R2153 in addition to grounding CGreset, then shouldn't there still be an error? Can you confirm that you did remove R2153 when you tested with R2054 grounded diagonally? If you did, try repopulating R2153 and testing the normal circuit.
 
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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...
JTAG Reset signal from user/external logic for all PowerPC processors.
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,
The test logic reset state is entered upon the assertion of the power-on reset signal, negation of JCOMP, or through TAP controller state machine transitions controlled by TMS. Asserting power-on reset or negating JCOMP results in asynchronous entry into the test logic reset state.
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.
So, yeah, I missed that part. I'll give it another go tonight.
I think theres a good chance it works this time. While I don't understand exactly what the reset signal is doing, the fact they changed it and it has to do with JTAG is very suspicious. So lets just copy the sony tech's work and see what happens. I have a good feeling about this one.
 
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I got locked in to a life or death battle with a JVC X'Eye. Someone threw it at the ground when it stopped working. Epoxied the drive back together, reset the spindle height, tuned in a new laser, retrofit a Playstation One door switch to replace the busted pin switch, 3D printed an adapter for the pin switch plunger so it hit the new door switch, replaced 315-5660 with one salvaged from a Genesis model 2 because the controller ports didn't work, sanded the corrosion off of the cartridge connector, and ran a few jumpers for corroded traces. I give up easy on most consoles and move on to the next one real quick, but when it comes to something like an X'Eye, I'm gonna fix that bitch no matter what it takes.

But anyway, that's all to say @RIP-Felix can you show me a picture of how the hell you have both probes connected at once and still have free hands to do anything else? Otherwise, I'm gonna have to grab those captures individually and y'all gonna have to use your imagination to line them up.
 
I just tape the cords to a plastic organizer tray and set that up on the motherboard to hold them in an upright position. Then I jam the ground spring into a GND VIA, it just barley fit's and provides a little support to hold the tip in the + via and probe upright. There's no trick, they are just balanced and it's a PITA every time...lol!
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I set the DC offset to -1.3 volts on both channels so I can easily find the signal. Then it's just a matter of messing around with settings until I get what I'm looking for or see something interesting.
 
I'm not sure if this is the correct thread to really post this in but I just found a DECHA00A with a syscon of 0C16, I don't really know how that's possible since it's supposed to only be COK-002 boards that have this...
Edit: found 3 actually
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@squeept probably has the most experience with this stuff but one thing I've been wondering about, are RSX revisions cross compatible and is there a chart that shows which models are interchangeable? All this research could essentially be for nothing if we can't source the RSX used in these models, and from what I can see the CXD5300DGB only appears in the refurb CECHA's.

On a sorta unrelated note I recorded my testing of the 90nm and 40nm CECHA during some normal tasks to show how they compare in terms of temperature, power consumption, and fan speed.
Both units used the same PSU, and both units were in a room that was exactly the same temperature (at least according to my temp probe)
 
I'm now less interested. Unless you need a reball or are nuts about power saving, the CELL Is a gas guzzler and won't do much

Sent from my SM-S102DL using Tapatalk
 
I'm now less interested. Unless you need a reball or are nuts about power saving, the CELL Is a gas guzzler and won't do much

Sent from my SM-S102DL using Tapatalk
The numbers might not look great but you need to remember that:
A. The RSX is the main cause of most PS3 issues.
B. This is with the stock syscon fan curve.
C. The thermal paste has not been replaced on the 40nm unit.
 
@squeept probably has the most experience with this stuff but one thing I've been wondering about, are RSX revisions cross compatible and is there a chart that shows which models are interchangeable? All this research could essentially be for nothing if we can't source the RSX used in these models, and from what I can see the CXD5300DGB only appears in the refurb CECHA's.

On a sorta unrelated note I recorded my testing of the 90nm and 40nm CECHA during some normal tasks to show how they compare in terms of temperature, power consumption, and fan speed.
Both units used the same PSU, and both units were in a room that was exactly the same temperature (at least according to my temp probe)
Impressive! You said You haven't delided/repasted? Not really a fair test using old vs. new paste, still the temps are quite good. If you delid and repaste you'll have the console open anyway. I would really like some pictures of the motherboard. All we have are some really grainy photos from a couple of users not likely to post anymore. We really need another set of good pictures. @DoublesAdvocate could we twist your arm to take some photos of the motherboard both sides? Especially the areas where the hardware changes are located.
 
Impressive! You said You haven't delided/repasted? Not really a fair test using old vs. new paste, still the temps are quite good. If you delid and repaste you'll have the console open anyway. I would really like some pictures of the motherboard. All we have are some really grainy photos from a couple of users not likely to post anymore. We really need another set of good pictures. @DoublesAdvocate could we twist your arm to take some photos of the motherboard both sides? Especially the areas where the hardware changes are located.
I'm hoping to find a second one of these before I do a full teardown and measurements since this one still has the warranty seal, ideally I'd like to find one that has already been opened but I think the chances of that happening are fairly slim. I think I might have a lead on a second one but I'm waiting for the seller to get back to me.
 
The numbers might not look great but you need to remember that:
A. The RSX is the main cause of most PS3 issues.
B. This is with the stock syscon fan curve.
C. The thermal paste has not been replaced on the 40nm unit.
Well if it was delidded and thermal paste changed maybe my stance would change, but as is unless you need a reball you should not go for it

Sent from my SM-S102DL using Tapatalk
 
Okay so I found someone selling a CECHA that was serviced (mobo replaced) on the 11th of June 2010, as far as I'm aware this would have been before 3.41 release meaning it's impossible for it to have the 40nm RSX have I got all that correct @M4j0r ? Is it possible that this unit would have the 65nm RSX instead?
 
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