PC won't POST after video card upgrade

[Joe McCall]

I bought a new video card recently. When I plug it in the motherboard fans spin up to their max and stay there. Some googling revealed that maybe the power supply wasn't cutting it, but I bought this PSU a while ago to avoid issues with cheap ones. I've unplugged any extra fans, drives, etc. to see if I could get to POST but no dice.

I've plugged in the old video card and this didn't happen, so there must be something about the new video card that isn't kosher with my current setup. Is it the motherboard? The PSU? Or should I RMA the card?

My setup:
CORSAIR CMPSU-650TX 650W PSU
DFI Lanparty UT RDX200 CF-DR
Athlon 64 Processor (I don't remember which kind, and I can't boot into my PC to check)
Old video card: Sapphire Radeon HD3570
New video card: Sapphire Radeon HD5870

Other details are available on request, but I think this should be enough.

Thanks in advance!

 

[Wildcard]

Hi,

I would try resetting the BIOS to see if that helps first. To do this, unplug the computer, then remove the CMOS coin shaped battery from the system board. Then hold the computer's power button down for about 10-20 seconds. Then put the battery back in and see if it will boot. I would try this first with the old video card, then the new, just to see if you can get it back up and running with last known good config.

 

[Joe McCall]

Reset the CMOS, but no dice. I've also been doing some further research. Here's what I've learned so far:

The secondary PCIE slot is probably useless to me. The BIOS only allows me to configure it for up to x12 link width, and the card seems to only support PCI Express 2.0 x16. Apparently the second slot is only useful in a crossfire situation. Bummer, because the primary slot blocks half the southbridge fan a little.

So I'm left with the situation where I can POST using the old card (but the card is damaged and makes artifacts on the screen), and I can't POST on using the new card. There's only one valid slot and my video card and keyboard are the only things plugged into the motherboard.

Admittedly I'm not as up-to-speed on video card tech as I used to. Did I buy an incompatible card?