I've installed memory before with no problems. However, I was about to order some memory from newegg, when I noticed a review that mentioned the particular RAM I was ordering didn't work in a specific HP model.
The motherboard I'm installing on supports PC4200 DDR2 240pin...standard stuff.
Am I not able to use any RAM module of that type? Do I have to use RAM specifically designed for HP computers?
It could be related to timing, density, etc... I had an old Compaq laptop that couldn't use memory that was too fast or too dense (but this was PC-100, not DDR2).
I want to say that DDR2 memory should be standardized enough to be supported, but you're talking about maybe $8 difference in price (when counting the lack of free shipping on the HP-sepcific). To me, its worth the $8 to get something that says it is supported. Otherwise, you could get the unsupported memory, and risk having to return it, incurring a restocking fee.
Voltage is probably a major concern, some memory requires more voltage than others.
If you buy memory that requires more voltage than the HP is set for, it won't work.
I doubt there are any options to change the voltage in the HP bios.