p55 motherboard won't recognize gpu or something?

[Oliver_Note]

I've already asked this question but I think I know what might be going on. I bought an Asus P7P55D motherboard from ebay not too long ago. The problem is I'm not exactly sure what's wrong. There are no integrated graphics and I can't seem get the motherboard to recognize my gpu. I have tried several gpus and it still doesn't seem to work. I can't tell if the motherboard is just broken or it has some serious problems recognizing the gpu since I can't see the bios. I've also had the same problem with a Gigabyte GA-P55-USB3 recently. The Gigabyte motherboard was working just a day or two ago in a different tower with the same i5 750 and ram. Is there any way to get a motherboard to recognize a gpu when I can't even navigate my bios? The gpus I've tested with is a 7870 and a 7970.

 

[CBender]

There is a problem with your board or the gpu. I have a P55 Gigabyte and works perfectly with a couple of cards. The highest i've used with it was a gtx 470. Nothing has changed within the gpus so drastically that a new card wont play in that type of boards.

I assume that you have verified that the gpu is working on a working system. Also the same thing applies for the cpu. If they do something is wrong with your system. The 750 doesn't have integrated graphics.

The fact that you don't get a post (get to bios) could mean a lot of things.