Can i connect different MHz Ram for same PC?

[killer bee]

Hi!
Currently my PC connected has 1GB "Kingston KVR 667 DDR2 Single-Channel 667MHz (PC2 5300) ram", but our area this Ram not available, I want connect another 1GB ram, but our area have "800MHz" upward Rams. So if i connect 800MHz ram to my PC what happen? Both ram old Ram and new Ram work together or not?
Is it effect my PC performance? If i connect different MHz ram can i increase my PC total Ram capacity to 2GB?

 

[stormy13]

Unless the sticks don't like each other or the memory controller is finicky, they should be fine together. Most time mismatched ram is OK and what happens is the faster stick will downclock itself and run at the speed of the slower stick.

If they won't play nice together then the only way to get to 2 GB is to get 2 sticks of the 800 MHz ram.

 

[killer bee]

Thanks! i'll try it!