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View Full Version : 360 RROD Err 1020 (E74) due to thermal paste?



The Error Guy
04-05-2011, 08:21 PM
I am fixing a 360 for a mate, it has a RROD. I took it apart and there appears to be no damage to the board, solder bridges or broken joints.

When I removed the heat sink I found that the CPU and GPU thermal paste had leached across them covering many of the SMD's on the surface of the chips. I have cleaned them up as best as possible (not perfect though) because other than that, this was the only problem I could perceive.

Now, with the HS held in place (and I have no thermal paste) I can get it to boot (no RROD... yet) and get to the part where the green lights flash and form the "ring". after that it overheats and shuts off. Idk if there is any video signal. I'm testing this on the bench with no screen attached. So it seems to boot then overheat since the HS are not very good without paste :D

Now, once or twice it has RROD'd during testing to see if it would continue to boot (with the HS being held in place) and i'm wondering if thats because of any excessive force on the HS or because the paste is randomly causing short circuits.

Is it likely that the paste is causing the problem? or because there is a bad joint under the CPU/other problem I can't see? atm I'm thinking its the thermal paste since it only started working after I cleaned it, or perhaps its because I took the clamps off.

I don't really feel like shipping it off to M$ since I have hopes the thing is jtagable and M$ will soon put that right :crying and I can't be bothered paying for it to be fixed.

Cheers

TEG

nedkelly
04-05-2011, 08:29 PM
The reason is that the xclamps did not make a good enough connection and the solder split causing the RRoD.
To fix the two I have I used a repair kit from TM that got rid of the xclamps and put screws in their place.
There was one part of the process where you have to over heat the chips with no fans to reflow the solder. If you want me to look for the vid pm me.

The Error Guy
04-05-2011, 08:58 PM
This thing has only one Xclamp on the CPU, GPU is fine.

I have vague suspicions the CPU might be running hot... too hot perhaps. it takes about 7 secs to get to the green ring, by that time the CPU causes the meths on the damp microfiber cloth i'm using as a temporary thermal pad to boil. I'm not sure if thats normal or not. Its around 75*C i'd guess (evap point of ethanol) Just seems to be a pretty quick temp increase.

I might be wrong though. I'll have to check with thermal paste on the die. One quick Q about reflowing the G/CPU, they are up to overheat temps but the actual chip is not that hot, I would have thought getting them up to a temp high enough to melt the lead free solder would kill them? It seems the auto cut off stops that.

The CPU's shiny thermal pad gets wicked hot, but the actual chip doesn't.

bob_doe_nz
05-05-2011, 06:56 PM
The reason is that the xclamps did not make a good enough connection and the solder split causing the RRoD.
To fix the two I have I used a repair kit from TM that got rid of the xclamps and put screws in their place.
There was one part of the process where you have to over heat the chips with no fans to reflow the solder. If you want me to look for the vid pm me.

^^^

Though I got my bolts from Ebay (http://cgi.ebay.com/10-sets-M5-screw-washer-XBOX-360-3-Red-Lights-X-CLAMP-/390311239729?pt=UK_VideoGames_VideoGameAccessories _VideoGameAccessories_JN&hash=item5ae05ce031) for a few bucks cheaper.

I think where you cover the processors, it's the CPU you left the fan on while the GPU is left for 8+ mins to 'reflow'

Agent_24
06-05-2011, 12:19 AM
If you want to do the solder reflow properly you should really use an infra-red BGA rework machine...