ATI HD2600XT

OK I just got this video card for a gift, Its a AGP powercolor HD2600xt 512 mb ddr2 with the HD 5.1 sound. now when I uninstalled my powercolor x1650 pro and installed the 2600 it screwed the whole windows up, all my drivers for the cd roms disappered. sound driver was gone as well, parts of windows were gone. so I did a fresh install of windows xp pro, when I put it SP3 it screwed up the video card, windows wouldnt come on because of a autostart command was missing. so I left out SP# and left in SP2. now I download the hotfix and was told to uninstall my soundblaster then install the video card. and everything works, but heres the killer, the box and card says 512 but the CCC and pcwizard says its 256mb, also its suppose to be pixel shader 4.0 but the CCC and pcwizard says 3.0 and the site CAN I Run It says I have 3.0 and 1 gig of video memory. now SP3 isnt a big deal right. and I did call powercolor but they never get back to me except once to say we dont carry 256 cards.I was told the HD2600xt was a very good card so My wife got it for me on newegg.com, my computer is a 2.6g p4-1.5 gig of pc400 memory, 250 and a 148 gig usb 2.0 hardrive, a p4m-80 biostar memory with via chipset. and a lcd monitor. Im going to get a new rig but this one has been faithful for a year and just wanted to upgrade the video card, the highest game I play is DEAD SPACE and Command and Conquer tiberium wars and some Chis JONES mods for legacy and bridge commander.the rest is movies and media/internet playing. nothing too serious until I can get phenom system.so please let me know if you know about these problems with this ati card and if SP3 pack is important.

so SP3 would be ok to download or just keep sp2. I just dont want to screw it all up again

too late, now the only problem I have is that the CCC isnt working at all. it takes a whole 10-15 minutes for CCC to install then when I restart the computer the CCC is Empty in programs.

yeah right now I got some errors and was told to reinstall the .net frame work and I did and it uninstalled and reinstalled in seconds but the CCC comes up with CLI.Implementation or one of its dependencies or mom.exe missing, so I installed the omega driver and it works fine with that, soI just dont know maybe I should have stayed with my x1650 pro. the only other thing is now on the drivers page it doesnt show my processor or driver for it but shows my computer with 2 processors a mcp and a acpi. but when I do a bensh mark it has almost the same before I did SP3, the omega drive shows a lost with some points, but maybe because of the settings and I have to get use to the omega ways instead of CCC.