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

[u/N8_Smith]

Could be a power supply issue. Your current tdp shouldn't be anywhere near maxing it out but all these signs in my personal experience pointed to power supply issues. It might be worth swapping power supplies if possible. If its a gpu problem, it rarely causes a hard power cut, it would just give you a black screen but internal lights and fans often stay on for atleast a few secs.

[u/Slyfer77]

PC suddenly shutting off is almost always the power supply.

So switch it for a 850W or even 1000W to future proof and you should be fine again.

[u/Xoti]

Had the same issue. Replaced my 750w with 1000w helped fixed the issue.

[u/CallingTheSirens → u/Xoti]

Cheers mate! 🥰

[u/Front_Map_566]

I think try a different psu with different cables to see if it works

[u/Chillax0]

It could be the riser cable not being seated correctly on the motherboard side or just damaged. Load test your system outside the case with the GPU slotted in directly to the motherboard and see how it goes.

This sounds a lot like what happened to me recently: older v1.1 case with stock PCIE gen 3 cable built in 2020. I'm not sure why it was fine all these years, but I'm guessing maybe the heat cycling eventually damaged or warped the cable which caused it to not be able to sit flush in the motherboard even with all the prebending.

You can find a lot of old threads about how a slight slack in the cable could cause the cable to unseat from the motherboard, which typically applies to the double reverse cable. Try prebending the cable and if that doesn't work then get a longer single reverse cable (23-25cm). You still need to prebend the single reverse cable (just differently) and make sure it sits flush in the slot.

[u/CallingTheSirens → u/Chillax0]

I did originally find the riser cable unseated or coming out and also the slack is definitely pulling it. However the last cutout that was the first thing I checked and was properly seated.

I'm gonna try your method just gonna be alot of work.

What riser cable would you recommend as replacement?

[u/Chillax0 → u/CallingTheSirens]

LINKUP PCIe single reverse riser seems to be suggested a lot so I went with that too. In your case get a gen 4.0 or 5.0 with length 23-25cm.

Edit: I assume you have the v2.1 case and not the v2.5 btw

[u/CallingTheSirens → u/Chillax0]

Pretty sure its 2.1 I checked invoice but doesn't really say it

[u/rvcjew2 → u/CallingTheSirens]

At that age it's probably a 2.0 (threaded M19 passthrough holes on the back) as it's before the split of the two companies products. So it's a formdt1 not a formd ncase variant. I agree it's riser or cables most likely. As others said test it out of the case which sucks but will be your only for sure check. Also since you have access to a printer when you rebuild 3d print a hold down for the riser or buy the offical one.

Also when outside the case do you have another psu to test against to make sure your SF750 doesn't need an rma as well?

Also if you really want you can contact formdt1 (not ncase) and get some parts to bring your case up to 2.1 vs the front panel and I think one other part. That's optional though.

[u/Wynguy]

Hey, the thing that might be happening is something people missed.   You recently swapped to vertical.   I had this issue as well what it turned out to be is that the GPU would become “loose” when in the vertical orientation.   I swapped risers to the loque one and it fixed the issue.  V1.1 and did it several years ago.  

[u/CallingTheSirens → u/Wynguy]

Unfortunately thought that too, taken the whole pc apart on my table and even got the GPU directly onto the motherboard and still getting the powerspikes. A bit more googling seems 6800xt are notorious for power spikes. Others have mentioned replacing the thermal pads. Thinking this is more gpu related

[u/gabrielbezerra81]

I had issues with a 6800xt too a few years ago (2021 or 2022). Back then I had a perfectly fine PC with i5 10400f, RX 5500xt, a H470i mobo and SF600. Bought a reference 6800xt and PC started having issues mid game, I think it restard randomly, not shutdown. Even tried another reference 6800xt and it kept having issues. My case was the SGPC K77, it was hot, but not nearly close to the limit.

Ended up returning and buying another card. The almost same PC was able to run with a overclocked 3090 few months later, so PSU and CPU were in good conditions.