Hey. I was planning to upgrade from my rubbish Radeon x600 to a better one, either a Nvidia 8800 or Radeon HD 2950 XTX (when it comes out). The thing is, the power connector to my computer says '250V' on it. Is this how much power the computer can take as the power cable was delivered with the computer? Do I have to buy another PCU wit higher voltage? And, if so, is the PCU external or do I have to remove the current PCU and replace it? Thanks in advance!

Also, can someone give me some advice about which graphics card to get? I'm thinking, if I don't have to buy a PCU, to buy a Nvidia GeForce 8800 GTS or GTX or an ATI Radeon HD 2950 XTX (codenamed R650 and scheduled for release in Q3 and I heard somewhere it was going to be released September 12th).

There minimum power supply requirement is 450 Watts. But if you have extra paraphenalias inside your cpu unit, it's better to get 500 watts or more.

Open your case and look for the label posted on the power supply unit. Compare the wattage value on it to the recommended power supply requirement as stated in the above.

250 volts is the input voltage value of your power supply. It means to say, you can plug it directly at 250 volts wall outlet.