accidentally posted this in hot deals "RAM"

Ok here is my problem

I bought sddram 128 mb from comp usa

I put it into my computer

I started it up

Then it said windows cannot start because some driver for
plug and play is missing

I call comp usa tech support they tell me to take out ym
oldest ram

no good

I put it back in and now my comp is refusing both sets of
ram i have 256 mb now


I need help badly