I am upgrading my 4+ year old PC by garbing a new mobo, memory and a vid card. I am reusing my PSU (475w CoolMaster) so I am trying to go from less power hungry components (my cpu choice is Athlon II 250).
It comes down down to my vid card choice, a MSI Geforce 250GTS (512MB) vs a MSI Radeon 4850 (512MB). The ATI card will cost me 30$ less from my combo deals, but I have never used anything but an Nvidia so far and know that ATI has historically had inferior drivers to Nvidia.
So pay more and stick to the geforce or save a buck and try ATI?
I'd save the money.
Just remember to fully uninstall and sweep the Nvidia drivers off the hard drive before installing the ATI ones.
In fact, with a new MB/CPU/RAM upgrade I'd suggest you fully format your hard drive and start from scratch anyway, that way you will know ALL the old drivers have been removed and Windows will be nice and fresh.
EDIT: Missed your posting of the cards in question. Neither looks too good from the reviews but the HD4850 seems to have more issues, mainly cooling, than the GTS250 which would be my revised choice.
ATI Drivers are what concern me most. I dont plan on OC'ing the cards so the cooling should be ok on both. I am mostly interested from hearing from someone who currently uses a 4850 (or similar) and how they are fairing. I know that the Nvidia drivers are solid as my brother uses a 8800GT w/o any problems and the 250Gts is derived from the G92 core.
Also I use and will keep using XP 32 bit for a while, also I am mainly use the pc for World for Warcraft (as far as gaming goes).
Currently have an XFX 4850, im using CCC 9.9 straight from the ATI site, it hasnt given me any issues, the driver issue isnt nearly as big of a deal as people make it out to be, yes new drivers may have issues with brand new games but i have been using ati cards for years and never had the drivers give me any issue.
also the 4850 will use less power than a GTS250 which will be helpful on your PSU, but i would suggest one of the ones with better cooling, unfortunately they cost more and tend not to be in combos.