My wife's PC was built in Akihabara at a store called Gtunes.
MSI 975X Platinum motherboard
Pheonix award bios V6.00PG
Intel 2.39Ghz Core 2 firstname.lastname@example.orgGhz
2GB DDR2 557Mhz RAM
Installed a brand new Hitachi 7200RPM 1TB SATA HDD prior to install of OS.
When I tried to use 4x2GB of Elixr 1.8V DDR2 800 windows 7 Ultimate 64-bit would not install updates properly. It kept getting errors during the installation of 13 critical updates. I was advised to just use the original 2GB of DDR2 557Mhz RAM and unplug all devices except for a PS2 keyboard. I did this and managed to install and properly update the OS to Windows 7 ultimate 64-bit.
It has been running stable for 5 days now with just 2GB of RAM.
So, now I've got 8GB of DDR2 800Mhz RAM sitting here and am wondering if I can safely install it in the motherboard without having some huge unrecoverable error occur. When I put it in the PC during the update of OS I got some serious errors including a lost boot sector manager which forced me to start from scratch. I really don't want to go through all that again.
I know the RAM is faster than what the moboard is rated for, but I was told that the BIOS would detect it as 667Mhz RAM and use it without problems.