I purchased an old laptop, its an HP zt1180. I know it's old and I'm saving up for a new machine, but its my workhorse and does what I want it to for most of the time.
I decided to upgrade the memory from 256MB and bought a 512MB memory stick. This particular laptop is upgradable to a maximum of just over 1GB. Its the right kind of memory (I ordered from 4 All Memory by using their memory selector tool) and seems to fit in the slot fine.
So, I put the memory in the slot and go to boot up the machine - the computer powers on, but the screen does not run through the boot process and remains unbooted (even though I know its powered on).
The laptop has two memory slots, the 1st one has the 256 system memory installed, and the second one is the one I'm trying to put the 512MB stick in.