PC won’t boot after upgrade

starmanwarz

starmanwarz

starmanwarz

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12 Jun 2006
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I installed my new 5800X3D, 7900XT and 32GB of RAM to my existing system (3700X, 5700XT, 16GB RAM, Corsair RM750X PSU) and my PC won’t boot.

So far I had my 5700XT connected with 1x8 pin cable which splits to 2x8 pins and it was working fine.

The 7900XT needs 3x 8pins and because I only had 2 I got one from my previous Seasonic PSU. I connected all 3 and nothing works.

After many hours of troubleshooting I discovered that when I have more than 1 cable connected to the GPU the PC won’t boot. I tried 3 different cables and 3 different PSU ports and the result is the same.

Now I tried booting with my old GPU, plugged it the way it was before, PC fans turn on but the GPU won’t.

Did I fry my PSU and possibly both my GPUs? Is there anything else I can try?
 
Journey said:
Did you update your motherboard BIOS before swapping the CPU's?
Click to expand...

Yes I updated to the latest version.
mickyflinn said:
You should never connect cables from a different psu without checking they are compatible, you may have broke your 7900xt.

Can you test the 7900xt in a different PC ?
Click to expand...
I shouldn’t have used the cable :(

I can’t test the 7900 due to insufficient PSU but I am testing the 5700xt at a friends PC.
LuckyBenski said:
Have you confirmed your motherboard is compatible with new CPU i.e. BIOS is updated?

Try the 5700XT to rule out the graphics card.
Click to expand...
The 5700 won’t power on, no leds and no fans working, testing at a friends pc atm to see if it works.
 
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Journey said:
If that is the newer CWT version is has 2x 6+2 pin PCI-E cables, but with 4 connectors, so should be enough to run the 7900XT without issue. Where did you connect the third cable from the old Seasonic PSU to on the new Corsair PSU?
Click to expand...
I did that and the leds on the 7900 turn on but not the fans. Also the PC doesn’t boot.
 
Journey said:
Did you do that before you tried the Seasonic cables though?
Click to expand...
I didn't.

So, the 5700Xt won't work in 2 different PC's. No leds, fans, nothing. I think I fried it.

On The 7900XT the leds are working, but not the fans. It also doesn't boot with 2 cables. I will have to either find a 3rd cable or get a new PSU.

The 5800X3D doesn't seem to be working either. I have updated the B450 Tomahawk Max to the latest BIOS, do I need to do something else?

I'm exhausted and very very sad atm, any other ideas?
 
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starmanwarz said:
I didn't.

So, the 5700Xt won't work in 2 different PC's. No leds, fans, nothing. I think I fried it.

On The 7900XT the leds are working, but not the fans. It also doesn't boot with 2 cables. I will have to either find a 3rd cable or get a new PSU.

The 5800X3D doesn't seem to be working either. I have updated the B450 Tomahawk Max to the latest BIOS, do I need to do something else?

I'm exhausted and very very sad atm, any other ideas?
Click to expand...

So you could have killed them then.

I guess all you can do is bench test the lot, with a known good PSU and GPU to see if anything else is dead. If you can't do that due to lack of parts etc. and you live close by I am happy to assist where I can. :)
 
starmanwarz said:
I didn't.

So, the 5700Xt won't work in 2 different PC's. No leds, fans, nothing. I think I fried it.

On The 7900XT the leds are working, but not the fans. It also doesn't boot with 2 cables. I will have to either find a 3rd cable or get a new PSU.

The 5800X3D doesn't seem to be working either. I have updated the B450 Tomahawk Max to the latest BIOS, do I need to do something else?

I'm exhausted and very very sad atm, any other ideas?
Click to expand...
As a way of breaking down the problem and hopefully regaining some confidence, I'd start by rebuilding the PC as it was. You can then swap components one by one to see what works.
 
Journey said:
So you could have killed them then.

I guess all you can do is bench test the lot, with a known good PSU and GPU to see if anything else is dead. If you can't do that due to lack of parts etc. and you live close by I am happy to assist where I can. :)
Click to expand...
I really appreciate it, but we are several thousand kilometers away!
 
LuckyBenski said:
As a way of breaking down the problem and hopefully regaining some confidence, I'd start by rebuilding the PC as it was. You can then swap components one by one to see what works.
Click to expand...
I did that, old GPU (5700XT) won't work, the rest are fine although having 2 sticks of my old RAM is giving me some problems for some reason so I only use one for now.

Basically it's old CPU/Mobo/RAM and a 970 GPU which I got from a friend. Unfortunately I can't test the 7900XT on his system. I did test the 5700XT though and it doesn't work.
 
did u reset cmos?

Also have a good look at the pcie cable ends, that u used and see if any damage to em. Bit surprised too that ur new psu didnt have enough pcie cables for the card?

If you got led warning lights do any flash and if not can u get a cheap pc speaker then u can see if any beeps come up and can troubleshoot that way.
 
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