Hello, I purchased more memory cards to UPGRADE my old computer. After I installed them I went to turn on my computer and i hear 3 loud beeps. The computer sounds like its running,and lights up but my monitor will not work nor will my keyboard or mouse light up.
Any ideas?

Thanks!!!! :-?Jediashe:

The three beeps likely means a memory error. If this is an old computer and they are SIMMs, you must install them in pairs, so you will have to install a fourth one. If this is a newer computer, you have either installed them incorrectly, or you have purchased the wrong kind of DIMMs. Make sure you have purchased the correct DIMMs. You might bring one that came with your computer to the retail store and show it to the sales person and ask her to find others that are of the same type (for example, if your computer has PC-100s then you need more PC-100 (or compatible) DIMMs.

DocAnd some older machines require low density (older) RAM rather than the newer high density chips.

Why don't you post your computer or mootherboard make/model as well as what you bought. Be as descriptive as possible.Hi, thanks, why WONT my monitor work now though?
This computer thats i;m having the PROBLEMS with is my daughters computer which she uses for games, its a hp pavilion 6640c , amd k6-2 500mhz processor, 64md sdram, (i have 15gb hard drive.
I have four slots for memory in the computer, i have three different memory cards. I got another card because the computer was saying it only had 52 megs of memory which it should have had more

here what memory cards i have:
pc100-322-620 (64mbs)
kvrpc100-/128-r

I;m not waht else you need:)

Thanks AgainYou can go to crucial.com to SEE EXACTLY what that machine needs. In your case it appears that machine takes a proprietary RAM that is unavailable, at least through them. On another site I found:

"Your Hewlett-Packard Pavilion 6640C only supports MODULES made with a specific type of chip. Should you find what seems to be the exact same memory elsewhere for a lower price, it is very possible that the cheaper memory will not work in your computer."

Here are some links to learn more. I am certain that the memory you got will never work. Good luck.

http://www.google.com/search?hl=en&lr=&q=pavilion+6640c+memory&btnG=Search

Th weird thing is that it was working fine today, It just gave me an error that it didnt have enough memory so i go tthe additional memory.
Now the monitor is not working at all. And i just tried to star up the computer and now there is no power at all... I dont know if i should just throw this thing in the garbage or take it somone and see if they can fix it...Make sure the one good (pre-existing) RAM is in there correctly and in the slot nearest the processor. Remove and reseat it. It could be that other things have failed to, but if it was working before....