Start FAH, Stop FAH, Start FAH, FREEZE!
 

Hey all,

It looks like I failed some OC attempt, and now I have some very strange behaviour with respect to Folding@Home on my Radeon 4870 (rig specs below). Any ideas on where I should start? It looks like my PC is still Prime95 stable but F@H hard-freezes it.

Last night, I was trying to push a little more of an OC out of my Phenom 9950 + Asus M3A78-T (both of which not the greatest overclockers), so I tried out a setting I believe was bus 230MHz, multi 12 (2760 MHz). To my horror, while I was running OCCT-Linpack, the CPU temp shot to 95 Celsius, and I discovered my CPU fan had stopped spinning!
After a CMOS reset (and verifying the fan was spinning), I tried again at 225 x 11 (ya I know it's below stock but I wanted to see if the HT link was stable), and that passed 8 hours of Prime95 Blend test, which I did under Linux 64.

When I booted back into Windows, I noticed the following behaviour, which persists AFTER a CMOS reset and setting everything back to stock:

1. Start F@H, and wait for it to start folding (as in GPU usage goes >50%).
2. Stop F@H by clicking CTRL+C (in the command line).
3. Within 1 minute, computer hard-freezes (no input, num-lock on corded keyboard unresponsive).

The above procedure is repeatable. I also tried refreshing the folding WU, and attempting to reinstall F@H.

Any idea why this is happening, and why it only occurs if I'm starting or stopping F@H?
What kind of tests should I start with to find the issue? I have a bunch of DDR2 + PCI-E rigs in my house so I can swap just about everything except the CPU into other rigs. (My dad's PC is AM2 but I doubt his motherboard can take a Phenom 9950 without failing spectacularly).

EDIT - looks like I didn't update my system specs, so I'll just post them:
CPU: Phenom 9950 125W
Motherboard: Asus M3A78-T
RAM - 8 GB: 2x OCZ Fatal1ty + 2x OCZ Platinum; all 4 sticks are rated 2.1V, DDR800 5-4-4-18
Case: Coolermaster Elite 330 modded with 2 extra 80mm intakes
HDD: Samsung F1 1 TB, Seagate 7200.11 500 GB
PSU: Seasonic M12 600W
GPU: Asus 4870 DK TOP, 512MB

EDIT 2 - It looks like I don't actually have to start F@H again to freeze the computer. It's just that stopping folding starts a "countdown" until it freezes my computer.

Go to the F@H folder (Windows 7/Vista: C:\Users\(your user name)\AppData\Roaming\Folding@home-gpu ) and delete the fah_core**.exe files, the Work folder, and queue.dat.

Make sure folding has exited before doing this. After you delete (or cut and paste to another location), run the F@H program again, and see if it folds properly.

Thanks for the reply. I actually reinstalled F@H (got rid of everything except config.dat, which I've completed about >100WUs under), and the problem remains. I'll actually update the prior post, because it looks like I don't have to start F@H again to trigger the freeze.

If the computer starts folding, then I CTRL+C the F@H, my computer will freeze within 1 minute or so. Now if I NEVER stop the folding, it looks like it's fine. (I'll see if I can complete an entire 511 without error, although when it finishes folding it will probably freeze.)

Uninstall the folding again, and before you install, check to see if the files and folders I mentioned are still there.

I'm using the command line client, so the WU files are kept in the install directory. I removed those as I uninstalled. (I also checked my AppData\Roaming, and there is no F@H folder there, since it is command line and not systray.)

You may still be right in assuming this is a F@H problem, since I can't seem to start the "death counter" with OCCT, but 1 split-second of folding will freeze my computer, BUT ONLY IF I CLOSE FAH.

EDIT:
Blaargh it looks like the issue was caused by AMD Overdrive... I that forgot I set a profile to try to set the core affinity for FAHCORE_11.
I disabled the whole "AMD Smart Profiles" thing and it looks like the issue disappeared. I'll leave it overnight (since my GPU can easily finish more than 1 WU in 8 hours) and see if that was the fix.