Mac Pro tube memory configuration question

Hi guys,
I've been searching around but have not found a good answer for this question about memory configuration. I'm about to spec out an 8-core, D700 Mac Pro, but I'd like to see if I can get 2x16 memory modules for a total of 32 GB at OWC with trade-in. That way, going to 64 GB in the future is more straightforward. Now my questions is: does it actually run in a more optimized way with 4x8 32 GB memory, with all for slots populated? I would like to go 2x16, but if that means lesser performance, I will stick with 4x8 modules. Thanks!

Shouldn't really matter. This RAM is plenty fast in this machine. The cards will all read/write data about the same speed. You may want to verify with OWC tech support. I'd actually be very interested in what they had to say about it.

My educated guess is that it would be technically faster with 4x8Gb, but I highly doubt you would be able to tell a difference, even when using tons of RAM on a complicated task. Like BenB said, the RAM on this machine is pretty darn fast. I doubt you'd be able to tell a difference unless you were using benchmark software measuring speeds down to the millisecond.

Hey guys, thanks for the replies. I actually chatted with OWC and they said pretty much the same thing. Technically 4x8 would be faster, but the real-world difference may not be enough to worry about. However, after thinking about it some more, I went just went with the default 4x8 Apple configuration because I didn't really want to deal with the trade-in at this time. I figure I'll do the trade-in if I need to go to 64 in the future.