Hi Chalenge,
Just passing on to you that while you're out shopping for a new DX 10 compliant vid card, there's been some issues w/ the later PCI-E 2.0 spec'd vid cards being truly backward compatible on some older PCI-E 1.xx spec'd mobo slots on both the Nvidia & ATI platforms, especially on PCI-E 1.0 & 1.0a spec'd mobo slots.
The problem seems to be much more of an issue for Nvidia cards than ATI cards & in the Nvidia camp the major brand that seems to have the issue is the EVGA brand, but other brands have had issues as well.
What is happening is that if the PCI-E 2.0 vid card is put in the primary PCI-E 16x 1.xx mobo slot the system will not POST. Take the card out of the primary slot & install it in the secondary PCI-E 16x (4x electrical) slot the system will POST & run just fine but at reduced performance levels. On another mobo the system would not boot up w/ the card in either slot.
The mobos mentioned in the thread "IP35Pro-PCIe 2.0 Compatibility Issue" on
www.abit-usa.com forums that were involved concerning this issue was the Abit IP35 Pro, the Abit IX38Quad & the Asus P5N/K series w/ a 7 to 1 ratio being teamed up w/ a Nvidia vid card as opposed to ATI. The issue is hit/miss on these mobos-some have no issues at all, some have major issues & the noted solutions have been just as hit/miss ranging from power supply replacement, mobo replacement, BIOS reflashes(vid cards/mobos) & vid card swappouts(mostly across brand names) w/ vid card swaps being the most effective method. The vid cards in question are the full PCI-E 2.0 spec(that is supposed to be backward compatible to PCI-E 1.xx mobo slots) vers not the PCI-E 1.xx vers vid cards that have PCI-E 2.0 support added.
You mentioned that you're using an Asus mobo that has the PCI-E 16x 1.xx slots so I wanted to throw this out to you (& anybody else) so that you may want to check your intended purchase for any issues or "fixes" w/ your PCI-E 16x 1.xx slotted mobo.
Not trying to scare noone off from using Nvidia-referenced vid cards either. Just passing information.
Hope this helps.