Rambus upgrade question

[Ring]

A friend has a Dell system with an Intel 850 MB. Board has 4 memory slots ..... 2 are currently filled with 2 128 mb sticks of Rambus PC 800. We'd like to upgrade the memory ....... another friend has 2 128MB sticks of Rambus PC 600 which I can get real cheap.
Question is ...... will it work? Any ill effects? Thx.

 

[Knightlife]

It should work, but all the RAM will run at the lower PC600 speed.