I want to upgrade the video card on my dell dimension 4700 system. The psu on my system is 305w so I know my choices are limited. The card I'm looking at is the ati hd 4670. Although the site state the requirement is 400w, I read all over that many people are able to use it at 300w. I know it also depends on the ammount of hardware that is installed in your pc. My pc is running a pretty light load as of now.
I basically have: intel p4 530 3.0 ghz, 1.5 gig ram,1 harddrive(5400 rpm at most), 1 cd/dvd rom and 1 dvr-rw/dvd+rw drive.
From what I can gather the 4700 psu has a dual 12v rails at 18.0amps a piece.
With the load I have right now is feasible for me to run the hd 4670?
That 4700 is a mid-tower case, so it'll fit. You might want to upgrade the RAM is you were installing the 4670. The Dell PSU's are usually underated so it'll run great. I have a 280W PSU in my Dell and my GeForce 8400GS demands 350W but it runs fine.
They "kinda" overstate them... The so-called "requirements" are guidelines which also have to include the absolute garbage power supplies out there that barely put out enough 12V power to make a car's headlight blink, as well as high-quality ones that give you plenty of umph for decent video cards. That said, your Dell PSU is fortunately one of the latter, and a 4600 series card should work well within it provided you're not running extra HDDs, fans, lights, and/or overclocking your system (much).