[Firefighter81]

I just replaced the ram for my Dell Dimension 4550. It was old so I Dell recommended that I update the ram, hard drive, video card. So I replaced the ram first. I had 256MB and tried to update with 2 512MB. Now computer wont turn on, it sounds like it is going to but nothing comes up on the screen. I took my old ram into Circuit City and had fire dawg guys cross reference with dell. Power supply on 2 months old. Does anyone know whats going on. I appreciate your help. Thanks

[Hughv]

What memory did you get? Your computer calls for DDR 2700/3200 depending on the FSB speed.
Have you tried just one stick? Will it boot with the original memory?
Have you installed the memory correctly?

[Flags]

You can ook at the diagnostic lights on the back of your 4550 and your manual will tell you what's wrong.

[Firefighter81]

I bought the DDR3200. Compatible with:
400MHz PC3200
333MHz PC2700
266MHz PC2100

My machine recommended the 2100, but I did try just putting one stick in then I tried the original stick of ram. The computer wont turn on at all. It sounds like it boots up but theres no signal to the monitor, then after about 5 minutes it shuts down. Also the A,B,C,D Lights in the back don' t come on at all either.

[Hughv]

You have the wrong memory, or defective memory.
Take it back, and go www.crucial.com and get what they recommend.

[Firefighter81]

I put the old memory back in and it still didn't turn on. Could I have fried something? Thanks for you help I really appreciate it.

[Flags]

See here for Diag Light interpretations http://support.dell.com/support/edoc...0/advanced.htm

[jazz3000]

What's your PSU size? Does bios require any change in memory? Can you clear bios and boot? Jazz

[Hughv]

Did the memory seat properly?
You should get two solid "clicks" as the memory is pressed into the slot.

[Flags]

I have had very few problems with Dell and new memory sticks. The Pc's seemed to accept any stick as long as it was the correct type (DDR, DDR2, etc.) The only stick I found that was incompatible with Dell was Centon. For some reason, it just wouldn't work. So we don't use Centon Ram.
Whenever you add memory to a Dell, upon boot, you get a message saying the Amount of memory has changed, press F1 to continue or F2 to enter Setup. Pressing F1 continues the bootup.

I think your problem is somewhere else. No Diagnostic lights indicates something is amiss.