I have had issues with my PC since last week when I "upgraded" from Core i7 3820 to Core i7 3930K on my
Gigabyte X79UD3 rev. 1.0, BIOS F11 I got the Core i7 3930K installed last Saturday with no issues I thought. The PC booted fine and everything seemed great - until I ran 3Dmark11. Suddenly the screen went black and the PC rebooted out of nowhere and had never done that before.
After the reboot I tried to check all power cables and reposition the SLi bridge to be sure all was fine and secure.
I ran Unigine Heaven DX 11 benchmark with MSI Afterburner open to check temps. They were all ok, but suddenly the GPU usage would go down from 95% to 30% and everything went sluggish and stuttered a lot and then the PC crashed again !.
I took out the top GTX 670 and ran SLi with the remaining 2 cards and every benchmark ran fine (Heaven DX11 3Dmark11).
I then I ran an OCCT CPU stress test for 10min just to be sure it wasn't the CPU getting hot and it wasn't.. Tempertures were never exceeding 57 degrees celcius at 3.5GHz (core boost enabled).
Then I thought I could be a bad connection, so I put the former top card in the middle and ran 3-way SLi again.
Initially everything ran fine when benchmarking, but then suddenly GPU usage plummeted from 97% to 30% and crash again !.
I then took out the middle card again, and then tested SLi in 3Dmark11 and Heaven DX11. No issues…at least so it seemed for that time.
Then I took out that card thinking it would be the culpit for the crashes so I RMAed it.
I did this based previous experience where one of my 3x GTX 580 in 3way SLi behaved exactly in the same manner and I got that card RMA'ed and got a new card and 0 problems.
But ironically... after RMA'ing the card I went home wanted to exclude the CPU as an issue and ran OCCT stress test for 1hour again and 0 problems.
hen I ran Unigine Heaven DX11 benchmark and no issues. Then I wanted to run 3Dmark11...and chrash again – black screen and restart !
Now I got the new GTX 670 card after the RMA installed it and tried with Forceware 306.23, 306.97, 310.70 drivers - however the problem was the same !
However I've isolated the problem and found the "solution" ! The Core i7 3930K can't do PCI-E 3.0 on this Gigabyte X79UD3 rev 1.0 motherboard
If I just install the nVidia driver and
DO NOT use the nVidia X79 PCI-E 3.0 patch, then there are
NO issues at all ! The GPU usage is top notch and FPS don't drop up and down, and I can actually hear the GPU cooler spin up because the GPU is working !
If I install the X79 PCI-E 3.0 patch then the FPS will drop up and down, and the GPU usage hops and dances between 90 to 20% usage untill 3Dmark11 or Unigine Heave DX11 crashes !
I then for testing took out the CPU and put in my old Core i7 3820 (haven't sold it yet).
And whatta you know rock solid with both PCI-E 3.0 and 2.0 !
I can only get PCI-E 3.0 to run solid and stable when I disable SLi and run with one card but the score is low in 3Dmark11
I run the patch in "administrator" mode. However the "revert" command I can't get the work at all from the CMD, so I have to uninstall and reinstall the drivers to get PCI-E 2.0 again - it's a pain !
The problem is the motherboard it seems !
I don't know if I should stay with the Core i7 3930K but then be stuck at PCI-E 2.0 or go back to 3820 and get PCI-E 3.0
What should I or would you do ? stay with the 3930 or go back to 3820 ?
In the F11 BIOS for the Gigabyte X79UD3 there's an option for enabling PCI-E modes ?
Is there any solution or fix ? I wan't PCI-E 3.0 on the 3930K and maybe I need another brand motherboard like Asus P9X79Pro I've looked at.
