I put 1G of RAM (Crucial) into my Compaq R3000 laptop (in addition to the existing 256M). I fired it up and it booted fine - maybe a little faster than before. I opened the System window, verified it recognized the additional RAM – 1.2G RAM present, no problem! Then I opened an internet browser window, closed it, and then walked away for a few minutes. I came back about 10 minutes later and noticed a blue screen with lots of text to read. I didn’t have time to read everything but it said something near the top of the screen about the Crucial memory, and something at the bottom about a memory dump! Then, a black screen came up showing:
For Realtek RTL8139… PCI Fast Ethernet Controller v2.13…
PXE-E61: Media Test Failure, check cable (flashing line)
PXE-M0F: Exiting PXE ROM (flashing line)
After trying to reboot it several times without any luck, I decided to remove the new RAM… re-booted… same problem pretty much – won’t boot.
I get a window that asks me how I’d like to boot (i.e. Safe mode, Safe Mode with networking, with command prompt, Last Known Good Config, Start Normally). None of these options work. They all start out with the normal Windows XP screen for about 50 seconds and then the screen goes blank/black (with the fan still running).
Also, on one of the reboots (after removing the new RAM) CHKDSK ran automatically and found corrupt file record segments which it deleted (I have some more details on this, if needed).

What’s going on here?

Right before I started this upgrade I told my son, “Adding more memory to a computer is one of the simplest things you can do”.

After reading "My PC won't start - Read this first!" it appears resetting the CMOS may fix this problem.

What's the best way to find the CMOS battery? Does it look like a watch battery, and is it the closest battery I can find near/on the motehrboard? Can I remove any battery I find anywhere inside the laptop????

Usually, when you reset something, information gets lost. Do I have to set anything back up after I remove/replace the battery?

did you unplug power and remove laptop battery before you install the ram .if not you could have caused a short and damaged the ram .
also the laptop cmos batter usually is wrapped in plastic and plugged into the motherboard via a small wire connector .