Wow..thanks for all of the responses. The notebook is about 5-6 years old. Its a HP Pavilion ZE5300 P4 266 Mhz. The old memory was 256 pc2100 DDR. The new memory is the same but 512 instead of...

Thanks for replying so quickly. This morning I made another bios update diskette and flashed it again. It took the upgrade this time...thank goodness. But now the memory I purchased wont work. ...

I recently flash my HP with a new Bios and now it gets to the XP screen and freezes up. I flashed it again just in case of some kind of error during the first flash, but still get the same result. ...