Computer only detecting 3 out of 4 GB of memory...

[Renegade23216]

I have four identical G-Skill RAM, 1 GB each. I have an Asus P5B MB.

I've had two gigs for the past year and it has always worked fine. I bought two more gigs and after installing them, only 3,001 MB is detected in the BIOS. Why isn't it detecting all 4 GB?

I tried installing just 1 GB at a time, and each stick works fine. I also tried installing one Gig into each of the four slots, and it still booted fine each time.

How come all four together aren't giving 4 GB?

 

[angelxplaya]

Do you have a 32bit or 64bit OS? 32bit only utilizes 3-3.5gb of ram I believe.

 

[faxon]

if he is using 4gb of ram it will still detect all 4 in bios. bad DIMM slot maybe? does it only happen when you use that DIMM slot? and which slot is it? try putting 3 sticks in with 1 in whichever slot you are putting the 4th stick into and none in slot 1 and see if it only gives you 2gb

 

[Fullmetal Chocobo]

Check the motherboard manual (or look around in BIOS) for a "memory remapping" option and see if that fixed the problem.

 

[n7]

Memory remapping.

For 64-bit, enable it.
For 32-bit, disable it.

 

[scruffypup]

There is also a slight chance that one of the slots is bad and it will still boot. Unsure by original post if you tried that.

Try putting in one stick in 1st slot, boot to bios and check
then second stick in 2nd slot,.. boot to bios and check
repeat for all slots,... you might find that when you put one in a specific slot you find the issue,...

worth a try 🙂

Actually rereading your post seems that you did that with 1 gb going to across,... I would still try it,... also try changing some of those ram related bios settings to see if maybe some bios corruption or a funky setting that is not intuitive,... mapping and remapping, dual channel on and off,... update the bios if not updated.