I have a huge problem I'm hoping someone can help me with or I'm off to Best Buy!

I purchased 512mb RAM for my Dell Dimension 4400. I bought it at Office Depot after they looked my computer up on their system to give me the right one. I opened up the computer took out my 128mb ram and inserted the new 512mb (I have 256mb in the other slot).

When I closed the tower and powered on my computer, my monitor gave me the "No Signal" screen as if the computer were on standby. The PC itself seems to be on, the green light is on, I hear the fans working, and the CD tray opens and closes.

I then powered off the computer and removed the new memory and reinserted the old memory. This did not correct the problem. I called the Dell support line and the technican had me remove and reinsert my graphics card. That did not work and he had no other answers.

I've tried my computer on two other monitors and gotten the same result. My only thought is that the memory somehow damaged my computer but I'm by no means an expert. Any suggestions? If I do need to replace something, will it be very expensive? Thanks.

Well, your first problem is that you have a Dell.

If the memory would have damaged your pooter, it wouldn't boot. You'd get a beep code, then nothing would happen. If the computer is POSTing and booting up like normal, the trouble can only lie in the graphical interface. Try using another monitor or another VGA cable, or a different video card.

BTW, don't go to Best Buy unless you know exactly what you're looking for. I've found that they very rarely know what they are talking about.

I've tried several monitors and gotten the same result.

What speed memory did they give you? According to the Dell support site, you should have 184-pin PC 2100 DDR266 memory in your computer. If they gave you DDR333 or DDR400 it will probably not work unless there is a Bios upgrade. The Intel site lists the 845 Chipset (the motherboard chipset Dell listed for the 4400) as supporting DDR200 / DR266 or PC 133 memory. You cannot mix these types of memory in the same machine. Also some motherboards are picky about RAM placement. Try putting the 256 Meg stick in DIMM slot 1 and the 512 in Dimm slot 2 (after you verify it is the right speed). You should also check the BIOS to make sure the memory speed setting in the Bios is correct (either AUTO or the listed speed of your memory). The memory should not have damaged your board unless it was the wrong type or forced into the DIMM socket incorrectly.

Took it to a shop and they found out the motherboard shorted. Thanks anyways guys.