Mixing DDR2 RAM, 800 & 667 bad idea?

[GARoss]

I've heard this can be done but at the expense of the 800 slowing down to match 667mhz. I have 2 matched 1gb, 800-PC6400s & 2 matched 512kb, 667-PC5300s. The PC5300s were given to me & I'd like to use them if I can, but, no big deal if I can't. Thought I'd ask before getting into trouble!
Thanks.

 

[Billb2]

It's not a yes or no answer.
It depends on the memory, motherboard and your skills in the BIOS.
Yes, it will run at the speed of the slowest, just put the slowest in the slot closest to the memory controller.
4 sticks, matched or not, will put additional strain on the memory controller. That's where being able to compensate for that in the BIOS comes in handy.

If you;re not comfortable working in the BIOS, just put them in. If it works, you're home free