A:Answer Hello,
Thank you for your interest in the Dell UltraSharp U2711 monitor. This monitor requires a DisplayPort or a Dual-Link DVI port on the computer in order to drive the high resolution of 2560 x 1440. You CAN use a plain VGA or DVI port to connect up with it but you will not get the high, sharp resolution mentioned previously, resulting in a blurrier picture.
In your case, I would add a video card to your HP that has a Dual-Link DVI or DisplayPort outputs on it. Since you have a 300 Watt power supply, I recommend a basic card, like a NVIDIA GeForce GT 430, or higher should do the trick.
Hope this helps!
JonathanNforDell
