You know about the power supply, there is a PCI-Express slot on the Intel 915GAV that you can use though there is the question of whether or not the card will fit in the case however. IOW, does your case have enough width for this big card to go in there and enough room on the end since it is a long card, IIRC.
There will always be some bottleneck somewhere, whether it be in graphics, bus speed, CPU or somewhere else. Another question is what kind of display do you have now in terms of resolution and the connection to your computer since I'd suspect that new card has a dual DVI for its outputs.
I was thinking of purchasing the card above and I was wondering if anyone could tell me if my PC is up to par to match this powerful card, I don't want to create bottleneck. Here is what i currently have--
Intel 915GAV 800FSB
2G PC3200 Memory
Intel 640 3.2Ghz Processor
Understandly I will have to upgrade my 350 watt powersupply.