Hd6870 no display

[awrenj]

Hi everyone. I recently got an hd6870, a used one from bestbuy. It made a funny highpitched noise when i first installed it. I figured it was a power issue, so i got a new 700w PSU. Reinstalled everything, still no display. I then put in my old video card, hd4670, and i got video. I went back to bestbuy, traded in the used hd6870 for a new one. Got home, installed the hd6870 and nothing. I then tried my old video card again, nothing...I tried switching from the integrated gpu to my old, to the 6870. I've also tried switching from vga, dvi, and hdmi.

I'm running a:
AMD Phenom II X3 2.2GHz
2GB DDR3 RAM
1TB Hitachi HDD
Asus M4A78T-E motherboard
Coolmaster 700W PSU
New card: AMD HD6870
old card: Asus HD4670

 

[awrenj]

I've checked all my connections and I've checked to make sure that the video card was seated properly.

 

[Supernova1138]

Your board does have PCI-E 2.0 support so compatibility shouldn't be a problem. Do you have both 6 pin power connectors connected to the card? If you don't the card may not boot. The only other thing I can suggest is to try reseating the card. It's possible it doesn't have proper contact in the slot. Another possibility is that you have hit some really bad luck and actually got two bad cards in a row. I think in the spec sheet it said your board supports Crossfire so you have two slots you could put the card into, try the other slot and see if it works. If your old 4670 isn't getting video either in either slot it could also mean that the PCI-E slots on your mobo aren't working properly.