I have just installed a new HDD and installed Windows 7 on it, so that I now have a dual boot system with XP 32 bit on the old drive and Win 7 64 bit on the new drive.
One of the reasons I installed Win 7 is that I want to use more RAM, but the BIOS is not detecting newly installed RAM. It only detects the old RAM, which is only 2Gig.
After having read several forum posts, I think I have narrowed the problem down to either of two possibilities: EITHER the new RAM is not compatible with my motherboard OR I need to update the BIOS (yes, I have checked that the RAM is properly seated, yes I have tried each stick of RAM in each different slot).
Here is my question: IF I proceed to update the BIOS to a version which is stated to be compatible with Windows 7 64 bit OS, will it prevent me from running XP 32 bit?
No, it won't. Incidentally, I have a second system that has 4 RAM slots. It has 2 184-pin DDR SDRAM slots, and 2 168-pin SDRAM slots; but, I can only put in 2 of the 184-pin, or 2 of the 168-pin sticks--I can't fill all slots, because the motherboard was designed for only 1 type, or the other. I don't know if you have that motherboard design, but I just thought I'd mention it, just in case.
Notice the spec says XP will not recognize more than 3Gig: http://www.asus.com/Motherboards/Intel_Socket_775/P5KEP...
"When installing total memory of 4GB capacity or more, Windows® 32-bit operation system may only recognize less than 3GB. Hence, a total installed memory of less than 3GB is recommended."
Make sure you're checking the RAM with Windows 7 up (System Information, or right-click on "Computer", and choose properties, to see the amount of "installed ram")
~~You shouldn't have to do a BIOS update (and it's fairly dangerous, also): the spec says it can accept 4 x DIMM, Max. 8 GB~~
Are you putting in DDR2 1200*/1066/800/667 Non-ECC,Un-buffered Memory?