Windows 7 - CPU Usage 100 percent after ram upgrade

Dell XPS M1210
Windows 7 ULTIMATE 32bit
Intel core 2 T7200 2.00Ghz

Upgraded memory from 2x1GB PC2 5300 667Mhz to 2x2GB PC2 6400 666 (800Mhz), and CPU usage hangs at 100 percent on boot with nothing in processes. Reinstalled windows twice with same problem.

I suspect I have to update my BIOS but cannot because battery does not take a charge.

My question is...is there a way to force the BIOS update without the battery?

Hello xps5 and welcome to Seven Forums.

Do you have an AC adapter for the machine? You may have one or more (new) memory chips that are bad. Try using them one at a time.

Yes, I do have ac adapter. The memory is new so I doubt that is the problem. I do believe the BIOS has to be updated to take the faster memory. So back to my original question...is there a way to update the BIOS without a battery charge?

You can safely operate your laptop using AC only. The battery can actually be removed if laptop is running off of AC. The BIOS settings should not depend on having a battery installed (at least the BIOS settings on my Dell Inspiron and Sony Vaio laptops don't require a battery to be installed.)

How to Run a Laptop Without the Battery | eHow.com

Sorry for not mentioning this earlier. You could open Resource Monitor to see exactly what's using your CPU. It may not be memory or BIOS related.

Resource Monitor

Why do you think you need battery to update BIOS? Actually running laptop just on battery during BIOS update is dangerous, if battery runs out of juice during BIOS update, your laptop is a toast. Of course the same is true if AC is shutdown and there is no battery backup, but in most places AC is reliable.
If the computer hangs up during boot, can you boot into windows at all? in safe mode? The memory could be not compatible with your computer, it could be bad (yes, especially brand new memory could be bad, one could assume old memory was tested in another system and it works), or there is some compatibility issue with 4GB memory on the system that can use only 3GB and possibly BIOS update can fix it, is that what it is? Is your computer even compatible with 2GB sticks? How about speed and timings? those are different from original and could create issues.
I would update BIOS using old, original memory. If the new memory has issues and it seems it does have random one, it could really mess things up during BIOS update, since CPU needs RAM to work.