I recently PURCHASED a 'Home Built ' computer that works fine, with DDR Memory that I wanted to upgrade immediately. It came with 256mb of PC2100 (2 X 128). My Motherboard is a " ASUS A7M266-M, per Everest diagnostic.

I was given the following information by various "knowledgable" people.

1) The MoBo would support no more than PC2700/333mghtz . . .
2) I could use PC3200/400mghtz (sticks were available free) but they would RUN at PC2700 speed, no harm, . . (underclocking ?) . . . and
3) If I installed PC3200, the computer would not even boot up.

Since they were free, I installed the PC3200 (2 X 256 matching) and the computer runs SUPER. I downloaded EVEREST to check on a few THINGS, . . .and under MEMORY BUS PROPERTIES it says my "Effective Clock" is 405 Mghtz. Does this mean that the computer IS RUNNING WITH FULL USE/SPEED OF THE PC3200 STICKS. ... or could the computer REALLY be running at PC2700 speed and fooling this thing, just because its picking up that the installed sticks are PC3200.

I hope this is CLEAR enuff for someone to respond . . How can there be so many VARIED OPINIONS from learned people on an issue that should be Black or White ? THX.The memory will run at the lowest speed of any of the RAM chips.

There is a maximum speed of memory that can be utilized depending on the system bus.

here is the recommended memory for that board:

http://www.crucial.com/store/listparts.asp?Mfr%2BProductline=ASUS%2B+Motherboards&mfr=ASUS&tabid=AM&model=A7M266&submit=Go

Thank You ! Who woulda thought I could install 2048mb of PC3200. ! I love the straight answers I get from this site. !!!!!You're welcome and thanks for posting back.