How can I determine if a upgrade video card (example geforce 8800) is compatible for a desktop computer?

I have a Dell XPS 400 desktop (Windows XP), and trying to upgrade from nVidia GeForce 7900GS (256MB)|||becareful buying an after market card for dell they are very propiretary but make sure it has the power to drive a big video card if by default it does not have the support for a 6pin or 8 pin pciEx video chances are it will not have the snot needed to run it yes you can buy converter power cords but it has just usually enough to run what was put in the case

anything extra maybe to much stress on it

hps for example have 230 watt psu and most 350-700 watt supplies dont fit

i know dell rewires their power supplies special and an off the shelf psu will nuke the motherboard

there are companies that build after market dell power supply units you might want to consider upgrading it|||It's kinda complicated so I'll explain briefly. You first have to figure out what type of card you're going to need, for example pci, pci x16, or AGP. The reason why is that different computers have different slots that would alow a specific card to be inserted into it so if you buy a wrong card you might have to return it and get the correct one. After that you can go and look for them online or at a store. Make sure that you do not mistaken PCI with PCI x16 or PCI Express 2.0 x16 because they are not the same. And since you have a Dell XPS 400 desktop I believe your slot would be a PCI x 16. I would recommend going to newegg.com for your shopping because their graphic cards are inexpensive and they're service is excellent.|||yeah just make sure you got a good power supply and room in your case for it and it appears you do. your power supply i would recommend be at least 500 watts some would argue with that but it's plenty of power especially in intel based systems where your vid card requires more power than the processor of course most powerful cards even require more than amd's even these days. also amperage output on your rail for your vid card supplemental power plug can affect it too gut given your system you should be good to go.|||you hav a PCI-E slot so all you have to worry about is having sufficient power for something like the 8800 GS you might want at least 350W but for something like 8800 GTX you would want 450W(make sure the psu fits)|||If you're using a GeForce 7900GS, then there's no doubt that you're able to upgrade to future GPUs. All modern cards today use a PCI-E slot, which is what you have. Just make sure you have sufficient power.