[geeks] Mac Pro 1,1 CPU Upgrade - failure?

[Mark Benson]

Update:

I dropped the Mac Pro back to it's stock X5130 CPUs, and reinstalled the 
heatsinks using a better (more modern) thermal paste, which when I used 
it on my games rig i7 dropped the CPU temps by 7-8C over the previous 
Silver-loaded stuff I was using. I also applied sparingly using a thin 
skim applied using an old plastic card.

I found after removing the heatsinks from the previous installation that 
good contact on the IHS surface just required the proper torque (tighten 
the screws until they squeak). Contact was even when they were 
subsequently removed after being tightened down properly, so I 
reinstalled them using the same torque technique.

The problem, however, persists.

Ubuntu Linux 16.04 runs fine, on a GUI Desktop. I left burnP6 running x4 
on all the 4 cores and also played some YouTube Videos, surfed and 
caused it to pretty-much roof out at 100% accross all 4 cores constantly 
for 10+ minutes. CPU core temps sat at mid-high 50s C and the CPU 
heatsink temps rose very quickly and then levelled out at low 30s C 
after about 6-7 minutes. Main and Exhaust fans were at a constant 650rpm 
(I think my Linux install currently has them hard-wired at that)

Nothing broke or fell over, but burnP6 may be a bit of a dumb process to 
test with in that it probably just spams instructions and doesn't look 
for responses. Any better ideas for actual stress benchmarks under Linux 
would be appreciated.

Mac OS X 10.6.8 lasted a good 10 minutes under duress with Geekbench run 
2x but, again, eventually face-planted and everything locked up, leading 
to complete loss of GUI responsiveness. I've tried installing a fresh OS 
X 10.6 install and that also locks and dies part way through the install 
process. Rebooting and restarting the install crashed very early in the 
loading stages. This is usually indicative of heat build up?

I'm stumped.

Either it's working right and Mac OS X is screwed somehow (but I 
remember running 10.6 on it and it was fine, plus it worked okay before 
I dismantled it!) or if it's overheating somewhere I don't see or I've 
broken it. I really dunno. Only things left are to see if either the 
Northbridge or Southbridge heatsink are loose or unseated.

I've tried 6 different CPUs (2 pairs of X5355s and 1 pair of X5130s), 
completely different sets of RAM DIMMs... I may even swap the Graphics 
board again and see if that's an issue (it didn't resolve it before, 
though).

As ever, suggestions appreciated.


-- 

Mark Benson
twitter.com/MDBenson