I have an ASUS M2N-E (yes out-dated, with an AM2 CPU).
I read that PCIe were backwards compatible, so I went out and bought a Radeon HD 6870 with a PCIe 2.1 slot.
I made the assumption that the card would work, but when I plug it in I get the VGA not detected beep warning from the mother board.
I've already verified the PSU (650w Gold+), the BIOS (tried several of the most recent builds), and had the go around with XFX for the graphics card, where they blame the mother board, and ASUS for the motherboard which just simply tells me the graphics card is too powerful and PCIe isn't backwards compatible.
Any thoughts before I go ahead and mail in the rebate for the card and buy a new motherboard?