[SOLVED] PC reboots on intensive graphics

[Jarda]

Title.
It all started some time ago, PC would reboot while playing certain games.
After trying everything I could think of, something sort of worked: Underclocking the GPU.

These are the main components:

• Gigabyte H97m-D3H MoBo
• Seasonic S12II 520w PSU
• MSI GTX 970 4GD5T OC GPU
• Intel i5-4440 CPU
• x2 G.Skill Aegis 4Gb DDR3 1600Mhz RAM

GPU has 1102 MHz base clock. I need to keep it at 482MHz max, or else the PC will reboot on most games, even Photoshop, etc...
One would think: The GPU is failing! / PSU can't handle it! / [-Something else-].

Yeah, but let's look more closely into it:
If I plug the same PSU + GPU in a G41 mobo with Core2Quad Q8400 processor and 2x2Gb DDR2 RAM I can play any game, run FurMark for hours and it will not fail.
If I plug a EVGA GTS 450 SC in the H97 mobo with Seasonic PSU it will run at 890MHz, I can play any game and run FurMark and it will not fail or reboot.
If I run the H97 mobo with integrated Intel HD Graphics 4600 and Seasonic PSU I can play games and run FurMark without issues again.

I tried to plug only one 4pin in the 2x4pin ATX-12V slot of the H97, PC boots normally but still reboots if I pass 482MHz base clock on GPU. Tried different PCI-e Gen. (1/2/3) settings on bios, raised CPU chipset voltage, GPU voltage and TDP, nothing helps.

I am really out of ideas, I have no spare compatible RAM sticks, but it seems the problem is the mobo.
It was sitting somewhere since it was refusing to turn on. In fact it was turning on, but speakers would short-bip indefinitely until all the fans stop and it tries to boot again. I've cleaned it and gave it a try and it worked again. Before it started failing to turn on, it was already rebooting, but at the time I could keep 580MHz on GPU. I went to a new house and it refused to boot again all of a sudden. I gave it some days, cleaned and it got working once more, only this time it accepts 100MHz less than before.

 

[hang-the-9]

You have a good quality power supply, so issue is likely with the video card. Need to test the card in another system.

 

[Jarda]

You have a good quality power supply, so issue is likely with the video card. Need to test the card in another system.

Well, like I've said I did that already, this is why I think the GPU is fine.

 

[Calvin7]

Use of memory modules sold as Single modules have no guarantee for compatibility if used in any configuration other than as a Single module. Use of exact match, identical, same thing - memory modules may increase the chances of memory working together over using random modules but have no guarantee to be compatible together.

Workarounds to get extra memory working together include:
Lower memory clock speed
Relax DRAM timings
Increase DRAM voltage

 

[Jarda]

These memory sticks were sold in pairs, inside a official G.Skill plastic case when I bought.
I didn't touched RAM related settings on BIOS, but I will try these workarounds then, thanks.

I am also about to plug a 2nd PSU(EVGA 430) dedicated for GPU just to see how it goes.

 

[Jarda]

I've installed a EVGA 430 PSU feeding the GPU only and the problem was gone.
It seems like either the Seasonic is failing(which I doubt since I've tested it along with the GTX970 on another mobo) or the mobo circuit somehow is failing to distribute power to the rest of the components.
Only way to know is to try another PSU with enough power, which I don't have right now.

 

[Dark Lord of Tech]

I would say it's the Seasonic PSU causing the issue. Latching off when under a little stress.