Although the newegg site doesn't specify, I have read that this particular card takes a minimum of 400w PSU, I've read a minimum of 350w...
I have a computer that I'm slowly starting to upgrade, my first purchase was the video card.
ASUS Grouper mobo with the 2.8g P4 Prescott.(not overclocked)
1 IDE CD/DVD Rom/Burner
1 IDE CDRom.
512mb of PC3200 ram(for some reason HWiNFO32 says its only 504mb,)
1 SATA 320gig WD Caviar HD(formats down to only 308).
1 Soundblaster Live! 5.1 Soundcard(Old school).
1 CPU fan
1 Case fan
Dual fan HIPRO 300w max output PSU
Will it run ok for atleast 2 weeks of moderate nex-gen games and heavy older games such as Dungeon Siege II and America's Army Special Forces 2.8.3
Getting a new barebones kit soon after realizing my shitty mobo won't support any good quad core intel duo 2's or any of the iseries
If your PSU is anything like this it should be fine for an HD4670; http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Much better card than a DDR2 9500GT.
However a video card is not where you should have started upgrading that thing. 512mb of ram is simply terrible these day, even for general usage, much less gaming. You should add at least another gig before considering trying to play recent 3D games on that computer.
The 9500GT uses very little power (50 something Watts if it's stressed) so even a crappy 300W PSU should be able to handle. Your CPU is a single core 2.8GHz P4 so it's not really too much of a power hog. Those still use less than 90W, but over 3.0Ghz, especially dual core P4s, they start sucking power . The 4670 uses a bit more power though, and considering that your 300W unit don't have much to spare I say stay away from it.
The 9500GT DDR2 is also a much weaker card. The HD4670 also uses very little power. It has no connector so it can't even possibly use more than 75w and tends to max out at around 65w and that's only under extreme conditions, closer to 50w for normal gaming.