Originally Posted by srcjenn
Being very new at this, how do I choose a new power supply that will work in my system. Currently there is a PS 6401-08HT (HP 5187-6134 OEM) power supply present. 400 Watt unit. I have also not found any dimensions in any of the product descriptions. Any help would be greatly appreciated.
PSU's are easy and hard at the same time. In psus the size is labled by types such as ATX, ITX, micro ATX, BTX, etc. Right now in modern days the most common are ATX. You have ATX so thats all you need to find as far as dimensions and obviously you need atleast 400W power.