Hey there i have a dell xps 420 computer and here is my computer info.
intel(R)core(tm)2 duo cpu E6850 @ 3.00ghz 2.99ghz ram 3.00 gb
system type 32-bit operating system
The new graphics card im going to get SAPPHIRE HD5850 1GB has to have 500 Watt Power Supply required and im not sure what kind of power supply to get and if i should just get a power supply that only has 500 watts or is it better to get more?How would i know if the power supply would fit in my pc?
What you need to do is find out how many amps the +12v rails have. If you look inside the case, the power supply specs should be listed on the black box in the corner. Chances are that it is not powerful enough, though, and you will probably have to buy a new one. Antec and Corsair are both really good brands if you do end up buying a new one.
if your computer didn't come with a dedicated card, there no chance your computer can handle a 5850, all oem all make their psu, just above the power requirements of the system, ususally +12v rails is next to nothing if there isn't a dedicated already in there