Hello, I don't know much about the PSU or the motherboard. My current PSU is 350watts. I just bought a video card that requires 400watts. Is it okay for me to change my PSU, or do I need more information about my PC?

Use this: http://www.extreme.outervision.com/... You don't have to know your motherboard.

Thank you very much. I went to the website and found what I needed. Thanks

Wattage calculators are pretty much useless because they don't take amperage into account. It's very possible that your 350W PSU is fine, provided it has enough amperage on the +12v rail. Your best bet though is to go with a higher wattage unit, such as 500W. That way, you'll have plenty in reserve in case you wanna upgrade further. Amperage is the key though. There should be a minimum of 30A on a PSU with a single +12v rail, or if the PSU has dual +12v rails, each should have 18A. Also, the unit should be of a reputable brand name & you should expect to pay approx $50 (or more) before any rebates are applied. Beware of units with high amperage on the +5v rail...20-25A is fine, but there's really no reason for more than say 30A. If you see 40, 45, 50A on the +5v, pass on it & keep looking. Here's a fairly cheap possibility: http://www.newegg.com/Product/Produ...