The ATI 9550 is a pretty good card. I found that card at Fry's for 129.99. (http://shop1.outpost.com}.
If you are just going to upgrade your current computer, that video card and max out the ram your computer can use will improve performance.
Since you are getting a new computer, you may want to consider upgrading to something with PCI Express 16 video slot. The video cards are more expensive but think of it as a computer to last for the next 5 years or so.
If you decide to go with nvidia type card, stay away from the Leadtek cards. Tried them, had nothing but trouble. Talked to a tech who said that they have poor quality control.
If you decide on the ati, stay with the cards that are produced and sold by ati.
Oh, and the question about 512 ram: 1)if you are talking about on the video card, only way to get that much ram is to link 2 duplicate video cards. To do that you would need to get motherboard that is SLI compliant for nvidia card or crossfire compliant for ati. (Note: I am using an ATI card on motherboard that is SLI compliant, works fine. If I wanted to add second ATI card would have to change out the motherboard) 2)If your talking about computer ram, yeh it will work but price of ram is getting cheaper by the day. I would say get max amount of ram that your current computer can use.
Just finished building new computer for myself. Gigabyte K8 Triton motherboard, AMD 64 processor, ATI Radeon 1800 video card, 200 GB Maxtor SATA drive, and 4 GB ram. Overkill for playing a game on, but I have had 4 accounts up and running at the same time with no lag at all.
Edited, Tue Nov 29 03:20:23 2005 by gwinrayven