BIOS can't see all installed RAM

Hi,

I've 4GB RAM installed on my board (Colorful, Phoenix award BIOS, PCIEX graphic adapter). The BIOS & OS report 3.4GB or so (cpu-z identifies the entire 4GB). I've googled and found there should be a memory remapping option somewhere in the BIOS, but was unable to locate it anywhere on my machine. Any clue will be appreciated.

TIA

forever, I believe the mem remapping was an option on some older BIOSs, not seen that much now. I believe that dropping Win 95/98 support made it un-needed, but not sure.

As PaCanc said, the BIOS should be showing the full 4GBs. As should the info on the POST when the computer boots. It's only 32-bit Windows that will only see 3.4 or so. It's the limit of addressable RAM allowed by 32-bit OS.

So you're just fine and enjoying all the RAM you can. And your money for 4GBs isn't wasted - your system runs much faster than if you had 2GBs and 3GBs would be slower due to losing dual-channel memory mode.

What motherboard/chipset do you have? It might not even be possible to use all of it with a 64bit OS. Linux has PAE support, so you can also address >4G with your 32bit Linux.

I'm with you gamerk - if the BIOS/POST is really reporting 3.4 then there's an issue.

forever - you said "memory reported by the BIOS after POST is 3406784K". Do you mean that this is the max count displayed by the memory test during POST? Did you enter the BIOS and see this number? Or is this a number reported by some program within Windows?

See my post above. Otherwise everything from here will be guesswork

Ah, a Chinese board - never seen it before.

They don't have a manual available to download, which pretty well kills our ability to walk you thru the BIOS.

Might recommend using a memory test on it, requires you to make a floppy disk or a CD. memtest86 is a good one. Won't change anything about how much RAM is showing but will make sure it all works.

If Windows XP reports over 3GBs of RAM, you should be in fine shape. go to Control Panel / System and read what it reports.

I think you're fine. Windows is reporting the correct RAM.

You might do some more digging into the BIOS to look for memory mapping options. That's about my only suggestion.

Forget about 32-bit and 64-bit OSes for now, that will come later, because if your BIOS says ~3.3GB then that's all your going to get.

Some things you can try...

1. Update the BIOS
2. Try resetting the CMOS.
3. Try testing each RAM module one at a time, ie only have one module installed.