I have couple question to ask
1. Am having PSU 425W standard from Dell, is it enough to support the above Graphic Card ?
2. Mobo - PCI express. Is it XPS 420 come with PCIE 2.0 that able to support the above Graphic Card ?
3. am having 1 750 hdd. and with Graphic Card upgrade, are the PSU able to Support another 1 TB HDD. i'm only have 1 DVDROM.
1. Way way more than enough.
2. PCIe is not 2.0but the graphic cards will run none the less
3. Again this will be no issue. Your ps has more than enough power.
The max u can put is GTX 260 .. not 280 or 9800 GX2. here my to do list currently.
Getting 525w PSU from Dell. - The PSU is for Precision t3400 . then i will decide wheter to get 280 or 9800 GX2.Plus .. install a couple of FAN.. that a must