Win 7 Pro 64 Bit only reading 3.25gb ram

I Have been running the RC of windows 7 for some time and had a problem with the amount of RAM it was reading. However I was told that it was a known problem and would be fixed in the final release.

Yesterday did a clean install of Windows 7 Pro 64 bit and Windows is only reading 3.25GB ram, they system has 4gb of ram installed.

Please help, system specs

Abit i45c motherboard
Intel duel core 2.2
4gb Crucial ddr
ATI Radeon HD3620
500 gb SATA drive (backup)
250BG SATA Drive (Main)
120 GB SATA drive (Music)

not other add on cards

Bios is up to date, however only limited tabs in bios, nothing relating to memory, on board graphics turned off in bios along with serial port, and printer port.

Edited to say, thank you for looking and any help would be appreciated!

That's odd... my first thoughts would be a BIOS issue. But if you've got the latest one and disabled everything then it seems unlikely. Are there any "Memory Remap" options in there? It may be worth resetting the BIOS options to default to see if that flips a setting that could be causing this.

I'll do some digging and see if I can find any other problems with this motherboard and 4GB ram.

Ah, it appears that this motherboard is based on the Intel 945 chipset... and although you may be able to run a 64 bit OS, your chipset is only capable of 32-bit memory addressing I don't see how you can get round this limitation without changing your motherboard.

Thanks for that, looks like a new MB for me then..

once question, If the motherboard and bios read 4gb (it does) the 32bit limitation is only in the os, will windows allocate the remaining ram to the video graphics? or does it use it at all?

Cheers