My friend has a Dell XPS and he is upgrading his RAM to 2 Gigs. He is taking his 512 sticks out and putting in 2 1 gigs. My laptop (a hp pavillion dv2000) uses Pc 4200 at 533mhz. His uses Pc 5300 at 667mhz. Would my laptop be able to use his RAM? they are both the same number of pins. Ive heard things online about things like the 667mhz RAM would like slow down to 533Mhz if you do something like that. Im fine with that, what I want to know is will it work and is it safe?