Windows 7 reporting 3.25GB when got 4GB and sometimes doesn't POST


Posts: 53   +0

I have an oldish athlon 64 on an Asus M2V motherboard and have just upgraded to 4GB (2x2GB) at 800mhz.

For some reason, the BIOS and W7 says that there is only 3.25Gb although windows does say "4GB (3.25GB usable)". The manual and "Tech Specs" on Asus' website says that it can support up to 8GB so I don't understand why it isn't recognising it. Any ideas?

Also, it is Win7 64bit Pro.

Another also, the pc sometimes doesn't POST when restarting and just sits there with all the fans spinning, but after a few tries it POSTs and goes into w7 with no trouble. I did memtest on the ram and it errored with both sticks in one way but not the other and so I currently have them in the way that they are working.

Thanks for your time


Posts: 1,880   +4
There is nothing wrong with the read out you are getting on your RAM as the missing amount will be in use by graphics or running processes.

Your boot problem is probably an early sign of a failing hard drive or RAM. Check your RAM configuration in the motherboard manual, there is often a right and wrong way to install the sticks.

The best test for the RAM is to run the PC with one stick at a time for several hours using memory intensive games or play a video. If errors occur the stick needs to be replaced.

Follow this guide to test your hard drive.

Identify the make of your hard drive and then use one of the links below to get the manufacturers diagnostic for ISO CD. Burn the image file to a CD, boot the PC with the disc in the drive and run the diagnostics. You first need to set the CD drive to 1st in the boot order in the Bios setup.

If you do not have an image burner use this free software to make the CD.




Toshiba Fujitsu:

Seagate, Maxtor & Quantum:

Western Digital:


Posts: 17,233   +234
If your copy of Windows 7 is 32-bit, it will only "see" a little over 3GB of System Memory. It your Windows 7 is 64-bit it will "see" the total 4GB


Posts: 10,606   +464
He said it was 64bit, but the behavior is exactly like 32bit.. So who knows. Perhaps he is right and its a new issue nobody has been able to resolve yet, or perhaps he's incorrect and he does have 32bit Win 7.


Posts: 17,233   +234
You can install a 32-bit OS with a 64-bit CPU, but you can't install a 64-bit OS with a 32-bit CPU... I really think Blekk has installed a 32-bit version of Windows 7 on his oldish athlon 64


Posts: 17,233   +234
Good idea SNGX1275, this just seems very odd. I hope Blekk doesn't crash the laptop doing a bios upgrade. The "also, the pc sometimes doesn't POST" concerns me too
I would try experimenting with the BIOS memory settings as I know "Memory Hole Remapping" may solve your issue if it is not already enabled or on your mobo model.


Posts: 1,880   +4
Click on Start, right click on Computer and select properties. It will list there under System, System Type if you have a 32 or 64bit Operating System. It will also show what your memory is and how much is available next to Installed Memory.

I think we need to hear from Blekk.


Posts: 783   +0
I checked the support page for the Asus M2V on the Asus site and found that a very similar question is at the top of the list of FAQ; so it appears others have encountered this issue. General discussion of this topic can be found here while a more in depth discussion of the subject matter can be found in the referenced Intel Memory Support Whitepaper. Section 3.1 of the whitepaper covers System BIOS Display of Available vs. Populated Memory which may help explain how the memory is being utilized.

Having some details on the system specifications would help, but this may be normal for this motherboard and chipset combination. Have attached a BIOS snapshot from the whitepaper that shows 800MB being utilized by system resources which might be typical.


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