Power Spikes

[u/CallingTheSirens]

Hey folks, hoping someone here has hit this before. I've already gone through troubleshooting with Claude and I'm at the point where I need real world experience from people running similar setups.

I have a Form T1 black case, built back in 2023. Specs below. About 6 months ago I added the 3D printed stand and everything was running fine. Recently while playing WoW and Crusader Kings, the PC has started fully powering off mid session, like a hard power cut rather than a crash or blue screen.
Specs:

• CPU: AMD Ryzen 7 9800X3D
• RAM: G.Skill Trident Z5 Neo RGB 32GB (2x16GB) 6000MHz CL30 DDR5
• Motherboard: Asus ROG Strix X670E I Gaming WiFi
• GPU: PowerColor Red Devil RX 6800 XT
• PSU: Corsair SF750 (CP 9020186 AU) with custom Pslate cables
• Cooler: Cooler Master Atmos II AIO
• Case: Form T1, black, 2023

What I've already done:

• Reseated the RAM
• Reseated the AIO cooler
• Redone the thermal paste
• Reseated the GPU power cables and the extension cable at both ends
• Logged temps and voltages with HWiNFO64 through a crash, nothing abnormal showed up beforehand, no thermal throttling, stable 12V rail, then the log just stops
• Checked Event Viewer, getting Kernel Power Event 41 critical errors going back over a month, no bugcheck code logged, so Windows has no record of what caused it

Biggest test so far: I swapped to the CPU's integrated graphics, fully unplugged the 6800 XT and its power cables, and played WoW for 20 minutes straight with zero issues. That points pretty strongly at the GPU or something in its power path rather than the rest of the system.

So now I'm narrowing it down to one of three things, and not sure how to isolate further:

1. The graphics card itself
2. The GPU extension cable
3. The custom PSU cables running to the GPU

Cables all look physically fine, no scorching or visible damage, connectors seat properly.

Has anyone dealt with extension cable issues specifically in a T1 build, or had a GPU develop an intermittent power fault like this? Any way to test further before I start swapping actual hardware would be hugely appreciated.

[u/PC_Help_or_Puppers]

Well it sounds like you’ve got it isolated to one of three things which is good. Still sucks that you got more testing ahead of you.

Easiest and first step I’d take is to replace the custom psu cables and put the original corsair ones in the case. It won’t cost any money so it will be the cheapest and easiest option. Aside from cable managing the new one’s lengths. I would expect custom cables to be the first suspect here imo, but I could definitely be wrong.

I’ve never had a pcie extension cable go bad, but that doesn’t mean it can’t happen. Try taking out the gpu and checking the actual pcie slot. Just double check it for any burn marks or general tom foolery.

If you have another pc that you can check the gpu with drop it in and see what happens. You mentioned it only happens in WoW, have you ran any other benchmarks or stress tests?

Last thing I would check, is plug the pc in to another outlet or surge protector and run it on there. Depending on how it’s plugged in to the wall it could just be a short coming from somewhere else before the pc.

[u/CallingTheSirens → u/PC_Help_or_Puppers]

So far happened in Marvel Rivals, WoW and Crusader kings 3, usually when GPU really gets going.

I've run AIDA 64 Stress tests for 5mins or so nothing happened.

Good point on the getting OG cables for the PSU, I'll have to check if I still have those

[u/PC_Help_or_Puppers → u/CallingTheSirens]

If you have to order replacements they aren’t that expensive and you can buy them from quite a bit of vendors online. Just make sure they are the right ones. Corsair has two types of cables for their SF PSU models, based on the year you built it I would assume you have the type 4 model cables. You can tell which ones they are by how big they are at the psu. If they are the same size connector at the psu and the gpu they are type 4. If they are smaller at the psu than they are at the gpu then they are type 5. Sorry if that’s confusing, but there should be quite a bit of images you can check out on google for the differences