MacPro 2.66 Memory Config. Adding?

[jazz1]

Okay, I've currently got a total of 5GB in. Two 2GB sticks, and two 512K sticks. The 2GB are in Riser B, DIMM 1 and 2. The two 512K sticks are in Riser A DIMM 1 and 2.

I've just ordered from OWC two 2GB sticks. So where do I install them, and do I need to move my original config. around to get the best performance?

I've enclosed the current layout as it looks before the additional RAM arrives. Thanks for your help. It has been awhile since I had to revisit this and don't want to mess it up.

I also have an ATI 3870 on the way. Maybe I ought to install that first and then tackle the memory thing after installing that so I can isolate any issues?

 

[emt377]

Put 2x2GB in riser A slots 0 and 1.
Same in riser B, slots 0 and 1.

Personally, I'd put aside the 512M sticks unless I can get a matching pair real cheap on ebay, craigslist, or something.

 

[jazz1]

Put 2x2GB in riser A slots 0 and 1.
Same in riser B, slots 0 and 1.

Personally, I'd put aside the 512M sticks unless I can get a matching pair real cheap on ebay, craigslist, or something.

Great idea on the 512's. I assume since they are not matched pair they slow things down right? Thanks for the help!

 

[Umbongo]

Great idea on the 512's. I assume since they are not matched pair they slow things down right? Thanks for the help!

I think they get slowed down with 512mb sticks as they are single ranked and not double ranked. Basically if you need that extra GB of memory then put them in, otherwise don't.

 

[emt377]

Great idea on the 512's. I assume since they are not matched pair they slow things down right? Thanks for the help!

Yeah, any unmatched memory runs at 50-70% of the speed of matched memory - for large data sets. With 8GB you'd probably never notice adding 1GB - unless your game or Photoshop, or whatever, happens to get its memory from that bank. In that case you'll wonder why everything is taking unusually long (or is it?) or your framerate is subpar (or is it?). Not worth the randomness IMO - and if it were me I wouldn't install it.

Here's some more info. It's still relevant, even though the prices mentioned are way outdated.
http://diglloyd.com/diglloyd/free/MacPro/memory.html

 

[jazz1]

Thanks!

Thanks for the information. I doubt I'm really bumping my head on memory once I get all of the 2GB installed. Four 2GB ought to do it.