Can i use 800mhz ram in a mobo that only supports up to 677mhz (is it backwards compatible)?

Question

i use xfx 610i mobo and want to run ocz sli ready 4gb 800mhz ram ( i know it wont run at 800mhz but will it work at all in the mobo)

Answer 1

Yes, you can use it, but of course it will only run at 677 MHz. Just make sure that it's the same type of RAM: 800 MHz DDR2 will in place of 667 MHz DDR2 RAM, but not as DDR or DDR3 RAM, and vice versa.  

Answer 2

No, the 800Mhz RAM is too fast for it.