Its 2GB of GDDR3 memory but does it have a VGA connector? MAIN QUESTION is.. will the PSU in the case be able to handle the GPU? its a 240W HP COMPAQ PSU which i think is quite legit and if it can run that HD3400 card i think it might just be able to run this card. P.S i wont be overclocking the processor but i might overclock the card a little (No volt increasing) So can i run the card? P.S does xfx supply a vga adapter with this card/ does it have a vga port
That graphics card has a VGA port, as you can see in the third image in that link you provided. However, you'd probably have to disconnect it when using the low profile bracket. You can buy a dvi to vga adapter plug or dvi to vga cable, but it looks like neither is included by XFX. Also, the XFX specifications for the low-profile 6670 indicate it requires a minimum 400W psu (can't find what the +12v rail requirement is for this card right now), but the small form factor model of the compaq dc7900 looks like it might not have room a standard atx power supply.
Since you apparently haven't bought the computer yet, I suggest looking for a different model with a better video card already included, or building your own - there are some sticky posts in the "Systems: New Build" section that can help you with doing the latter and with asking for advice about it.
400W is the minimum safe power supply, I think. I can't stop you from trying it, but it's risky. Since it's an LGA 775 cpu and comes with DDR2 ram, I'm guessing that's a clearance model. If you're only gaming at 1280x1024, you might see if the performance is acceptable using the hd 3400 that it comes with before trying to upgrade to a 6670.