Not Sure What's Faulty-Power Supply, Motherboard PCIe slot, or GPU.

Skill · 08-16-2015

So I went to upgrade my computer.
My old specs:

AMD Radeon HD 7870(2x 6-pin connectors)
AMD FX 6350
ASROCK motherboard
700W PSU

The new Setup:
Intel i5 6600K(stock speeds)
ASUS Pro gaming motherboard z170
Same PSU
Same Video card

The old system was 100% functional prior to taking it apart to build the new one. No issues, handled games under 100% GPU load just fine.
When I assembled the new system, only the onboard VGA port worked. The GPU fan would spin, but the GPU would not output an image. I tried installing windows and installing drivers, but the GPU did not show up in the device manager, and the driver installation failed when I tried to get the correct one from AMD's site.

If I tried unplugging the VGA with the DVI plugged in, the system would just shut down. Upon turning it back on, i would get a notification from the ASUS motherboard that it detected a power surge and shut down to prevent damage(I'm using a surge protector).

So I tried putting a spare GPU(an old radeon 6750) into the same PCIe slot. This GPU does not require any external power connectors. It didn't work. So I then tried that 6750 on a lower PCIex8 slot, and it worked, displays video and everything. Unfortunately, the AMD Radeon 7870 won't fit in that slot because SATA ports are in the way and block it from fitting.

So, I decide the PCIe slot is faulty, and reassemble my old setup(using the usual AMD Radeon 7870. After everything is setup up properly, and I boot. It boots fine, image from the GPU and everything The system shuts down every few minutes. I'm a bit puzzled, until I start smelling a subtle smoke smell if I stuff my face inside the case. I later turn it back on, and I realize the GPU fans never spin on the 7870, while the image works.

So I put the spare 6750 in, and it works flawlessly. No reboots, fans are spinning, and I'm actually posting this from this computer(I can switch to phone or laptop if needed).

At this point, I don't know what's broken. It might be my power supply, that could be supplying dirty power to the PCIe lanes, and the motherboards handling i different. It could be my video card(the 7870), that fried the new PCIe slot. It could be the PSU, that fried both the PCIe slot and the GPU. It could be the motherboard(with a potentially faulty PCie slot, that fried the GPU.

Unfortunately, I don't have a power supply tester or multimeter, and there's no stores nearby that sell them. I can take it into the PC shop I work at tomorrow to test the PSU(there's a PSU tester there and spare parts), but I'm hoping to get this fixed ASAP as I have limited time to RMA the board.
Any ideas?

hosler · 08-17-2015

Might be psu not dishing out enough power. Try removing not needed stuff from psu like cddrive.

08-16-2015	1
Skill The Unwanted Critic Join Date: Sep 2011 Posts: 3,639	Not Sure What's Faulty-Power Supply, Motherboard PCIe slot, or GPU. So I went to upgrade my computer. My old specs: AMD Radeon HD 7870(2x 6-pin connectors) AMD FX 6350 ASROCK motherboard 700W PSU The new Setup: Intel i5 6600K(stock speeds) ASUS Pro gaming motherboard z170 Same PSU Same Video card The old system was 100% functional prior to taking it apart to build the new one. No issues, handled games under 100% GPU load just fine. When I assembled the new system, only the onboard VGA port worked. The GPU fan would spin, but the GPU would not output an image. I tried installing windows and installing drivers, but the GPU did not show up in the device manager, and the driver installation failed when I tried to get the correct one from AMD's site. If I tried unplugging the VGA with the DVI plugged in, the system would just shut down. Upon turning it back on, i would get a notification from the ASUS motherboard that it detected a power surge and shut down to prevent damage(I'm using a surge protector). So I tried putting a spare GPU(an old radeon 6750) into the same PCIe slot. This GPU does not require any external power connectors. It didn't work. So I then tried that 6750 on a lower PCIex8 slot, and it worked, displays video and everything. Unfortunately, the AMD Radeon 7870 won't fit in that slot because SATA ports are in the way and block it from fitting. So, I decide the PCIe slot is faulty, and reassemble my old setup(using the usual AMD Radeon 7870. After everything is setup up properly, and I boot. It boots fine, image from the GPU and everything The system shuts down every few minutes. I'm a bit puzzled, until I start smelling a subtle smoke smell if I stuff my face inside the case. I later turn it back on, and I realize the GPU fans never spin on the 7870, while the image works. So I put the spare 6750 in, and it works flawlessly. No reboots, fans are spinning, and I'm actually posting this from this computer(I can switch to phone or laptop if needed). At this point, I don't know what's broken. It might be my power supply, that could be supplying dirty power to the PCIe lanes, and the motherboards handling i different. It could be my video card(the 7870), that fried the new PCIe slot. It could be the PSU, that fried both the PCIe slot and the GPU. It could be the motherboard(with a potentially faulty PCie slot, that fried the GPU. Unfortunately, I don't have a power supply tester or multimeter, and there's no stores nearby that sell them. I can take it into the PC shop I work at tomorrow to test the PSU(there's a PSU tester there and spare parts), but I'm hoping to get this fixed ASAP as I have limited time to RMA the board. Any ideas?

08-17-2015	2
hosler Banned Join Date: Sep 2012 Posts: 1,059	Might be psu not dishing out enough power. Try removing not needed stuff from psu like cddrive.