Is RAM "backwards compatable"?

[luckyedboy66]

i have a laptop that has 2 sticks of 512 DDR2 5300 667mhz ram (1gb total), and im considering upgrading to 2 sticks of 1gb (2gb total). my friend has a 2 yr old Viao which crawls, so im thinking about selling him my old ram, but his takes DDR2 4200 533mhz RAM.
my question is will 667mhz RAM work with a 533mhz ram computer??

 

[Geoff]

Yes DDR2-667 will work in a computer that can only support DDR2-533, it will just run at lower speeds.

 

[luckyedboy66]

Yes DDR2-667 will work in a computer that can only support DDR2-533, it will just run at lower speeds.

sweet. i was petty sure it would run slower...lol. thanks 4 the info.