Question PCIe x16 slot died ?

[deam0]

Hey Everyone,

This is my first time actually posting here, though I've used this as a resource for years.

With a work benefit program I was given some money for home office supplies. I thought this would be a great time to get some nice cable mod cables and a fully modular PSU. Please note there was nothing wrong with my PSU, I've had it for about 5-6 years Corsair TX850M. It's been a great PSU, no issues what so ever but it's not fully modular so I always had those clunky black wrapped mustard cables.

Yesterday I had the day off so I figured it would be a great time to change out the PSU and cables. I turned the PC off, turned the PSU off, cleared the power to the PC by pressing the power button multiple times and holding for a few seconds. Replaced everything in about 30 minutes. It looked beautiful, and I was pleased. I closed everything up and plugged it back in. I didn't realize that the new PSU was already swapped on(or I mistakenly hit the switch) when I plugged the power cable into the PSU the lights on the mobo flickered on. I turned on the machine and everything lit up, (mobo, gpu, ram, case fans etc.) I waited for the display to come on but it never did. I noticed that my fan lights changed over to the color scheme I have them set to in icue so I knew the machine was making it past post to boot. I thought maybe the monitors were just not turning on so I manually turned them on but no signal. Turned the machine off and tried about 2-3 more times, still no display. I ended up pulling the PSU back out and realized that one of the PCIE 8 cables for the GPU wasn't plugged in to the back of the PSU(it's a 3x8 GPU.) I thought that might be my issue so I plugged it it and tried to power the machine on again, same results. To make 4 more hours a short story, I noticed that the VGA light was lit on the motherboard and in the end I found that even with the old PSU and cables the PC only worked when the GPU was in the PCIEx4 slot.

My question is, would this confirm that the slot itself died via some issue with the PSU being flipped on when I originally plugged it in, or that I only had 2 out of the 3 power cables connected on the first go? Or could there be something wrong with my GPU now/is this PSU or the cables at some sort of fault here? My intention is to sadly go buy another mobo, this one is only a year old to the day. Any insight would be greatly appreciated. Thanks!!!!

I'm not new to PC building/troubleshooting by any means but I haven't experienced a PCIEx16 slot failure before. I've only seen a slot fail when a mobo was very old or someone tried jamming their card in the wrong way/pulling it out etc. I confirmed when ordering the cable mods that they were designed for the RM850X.

Relevant specs?:
i9-10900KF
RTX 3080 FTW 3 Ultra
RM850X PSU
Z490 Aorus Elite AC

 

[Lutfij]

Welcome to the forums, newcomer!

Please note there was nothing wrong with my PSU, I've had it for about 5-6 years Corsair TX850M.
You need to keep in mind that the internals of the PSu are what get put under stress, so even if the PSU looks clean on the outside with spruced up cables, the capacitors give out due to wear and tear, eventually the PSU ends up delivering less power than it was advertised to.

I'd try and disconnect the system from the wall and the display(s), then remove the CMOS battery from the motherboard, see if that helps with POST.

If you're able to get into BIOS with the other slot, can you check and see what BIOS version you're on at the time of writing?

 

[CrymsonRanger]

I actually have a very similar problem where the system will only boot to windows with the gpu in a 4x slot. I have swapped everything except the GPU and CPU, Ram, Mobo, PSU, nothing helps besides keeping the GPU in a 4x slot. System won't even boot to installation media with it in a 8x or 16x slot. I know this doesn't solve your problem just thought I'd pass along my experience and suggest maybe starting with the CPU or GPU if you can beg borrow or steal either even just briefly for testing.

 

[deam0]

Welcome to the forums, newcomer!

Please note there was nothing wrong with my PSU, I've had it for about 5-6 years Corsair TX850M.
You need to keep in mind that the internals of the PSu are what get put under stress, so even if the PSU looks clean on the outside with spruced up cables, the capacitors give out due to wear and tear, eventually the PSU ends up delivering less power than it was advertised to.

I'd try and disconnect the system from the wall and the display(s), then remove the CMOS battery from the motherboard, see if that helps with POST.

If you're able to get into BIOS with the other slot, can you check and see what BIOS version you're on at the time of writing?

Hi! and ty for the response!

I think I may not have conveyed the situation properly. I can get into the bios if the card is in the x4 slot. I cannot get any display if the card is in the x16 slot.

Also about the PSU, there was no issue with that PSU, everything worked fine in it. The issue occurred when I swapped out that PSU for this new rm850x and the cable mods. I'm just confused how I would have shorted out the pciex16 slot when replacing the PSU and cables.

Hope that makes sense, again thanks for the reply.

 

[CrymsonRanger]

The only worthwhile thing I can add is that computer hardware can be finicky sometimes and can fail for what seems like no reason at all.

An example would be that back at the dawn of time me and a Co-worker spent a week tweaking and testing a big network server for an important client. Day of the install arrives and we get the truck all packed for the 2.5 hour drive across the state to install it then we start boxing up the equipment to go with the server. On a whim I said we should fire up the server just to make sure everything was spiffy. This was a five minute process back in those days. Wouldn't you know I plug it in, flip the power switch and.... nothing. Damn thing was dead as a doornail. Somehow sitting there unplugged from the night before the power supply had geeked and we had to wait a week for a new one to come in.

TLDR;
Strange things just happen with pc hardware sometimes.