You neglected the forum post.

"Tip: If you are asking for help to troubleshoot a computer-related problem, please be sure to include all the necessary information (ie: operating system, model number, hardware, software, etc) that will help others identify your problem for a speedy resolution."

No make/model/urls also known as DETAILS that could tell what's up.

But here's my guess.

1. The BIOS is out of date.
2. The new sticks are incompatible.
3. You have RDRAM and didn't put in the CRIMMS.
4. The new sticks have a defect.

Bob