so i have a brand new bone stock dell vostro 420 intel core 2 duo e7400 2.8 ghz 80 gig hd 3 gigs of ram with a stock 256 meg ati hd 3450 with hdmi ( i only got the dell because i got it brand new in box for $375 cash no tax and its main purpose is for htpc use with some gaming on the side)
the question is what is the best video card i can slap in there with out replacing the power supply if i need a new psu that no big deal but i realy do not want to as this computer is so quiet i can not even notice its on
no nvidia (they are way overpriced)
hdmi with audio is a must
passivly cooled would be nice but not a must
One of the options for that computer is a 9800GT I'd say the best you can do is a Radeon 4770. Even though the 4850 is a bit faster it uses significantly more power (the 4830 uses about the same so don't get that either). Even though you could technically even put a Radeon 4870 (it's not going to use all 350W with a 4870) as long as you have enough amps on the 12v rail, it would be stressing your PSU which would lower it's life span. Go with the 4770 and be happy. If you want to put in anything more powerful it's advisable that you upgrade your PSU first.