Is ddr2 speed backwards compatible?

[Mercmaster]

Hi folks,

Got a quick question, is ddr2 speeds backwards compatible like regular ddr?

I'm looking to add some more memory to two Dell optiplex systems at work, they both have single 256 mb sticks of ddr2 400 (pc2 3200). The price for a gig (2x512) of ddr2 533 (pc2 4200) is cheaper than the ddr2 400 sticks, so I need to know if these 533 sticks will run at 400 speeds if I buy a gig and install a single 512mb 533 stick in each system with the existing sticks of 256mb ddr2 400.

Thanks in advance.

MM

 

[FrozenCanadian]

I know you can run 667 at 533, and 800 at 667 and 533. I've never heard on ddr2 400 though but it would work the same. The only thing I'd say is go to a memery makers page and make sure their ram works with a dell.

 

[esun]

It should work just fine. I also wasn't aware there was a DDR2 400, but a search on Newegg shows there definitely is. If it wasn't compatible, they wouldn't have called it all DDR2.

 

[Mercmaster]

Thanks for the input guys, I think I'll order a set of the 533 ram and give them a shot.


MM

 

[imported_rod]

There definately is DDR2-400, but it has no performance gain over DDR400.

DDR2 will run at slower speeds, as long as it's all still DDR2.

RoD

EDIT: To answer your question: YES, DDR2 is backwards compatible.

 

[Aluvus]

Yes.

But for your own sake, you may want to double- and triple-check to make sure that you need DDR2.