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damiensmunki · Apr 14, 2007, 03:08 AM

I'm noticing a lot of slow down with my Mac Pro. I've got 3 GB RAM and 2.66 Ghz processors. However, whenever I load my iTunes library (27.5 days lossless files), my RAM is filled with image files. Can anyone tell me if increasing the HD speed would affect this performance? If not, what levels of performanc would the increase in speed affect?

aehaas · Apr 14, 2007, 09:12 AM

I seem to remember a KB article that said the best RAM utilization occurred by using at least 4 slots filled. Are you using 3 1Gig RAM modules? If you are and fill the 4th slot with another gig then the whole computer should speed up seemingly.

aehaas

mduell · Apr 14, 2007, 09:41 AM

4 slots filled maximizes the memory bandwidth, but I don't think damiensmunki is having a memory bandwidth problem. Also his 3GB is probably 2x512MB (stock config) + 2x1GB.

I'd add more memory and a faster hard disk, but I can't say for sure which will help more.

bearcatrp · Apr 14, 2007, 04:00 PM

So filling the first 4 banks is good for bandwidth. Is it ok to leave the other 4 banks empty? I just snatched the 2 ghz macpro refurb yesterday and want to buy my ram 2gb sticks at a time when I can afford it and plan on 2 2gb sticks for the first upgrade. As time goes on and the price goes down, and I can afford it, I'll fill the other 4 banks. But if I loose on performance because the other 4 banks are empty, then might go after 1 1gb stick at a time until all are filled. Just looking for clarification. Thanks.
Randy

aehaas · Apr 14, 2007, 04:45 PM

The article here is worth reading:
http://docs.info.apple.com/article.html?artnum=304492

And page 32 of the manual states that memory must be installed with matching PAIRS:
http://manuals.info.apple.com/en/Mac_Pro_User_Guide.pdf

aehaas

Xyrrus · Apr 14, 2007, 07:24 PM

Originally Posted by bearcatrp

So filling the first 4 banks is good for bandwidth. Is it ok to leave the other 4 banks empty? I just snatched the 2 ghz macpro refurb yesterday and want to buy my ram 2gb sticks at a time when I can afford it and plan on 2 2gb sticks for the first upgrade. As time goes on and the price goes down, and I can afford it, I'll fill the other 4 banks. But if I loose on performance because the other 4 banks are empty, then might go after 1 1gb stick at a time until all are filled. Just looking for clarification. Thanks.
Randy

There is actually a slight decrease in memory performace when all 8 slots are filled. However, in most cases the memory performance will be offset by the systemwide gains of having more memory available (unless you're never using it - but if you're not using it, why buy the extra memory!)

RAM must be matched in pairs, but not pairs of pairs. 2x512 and 2x1GB is perfectly acceptable. There would be no performance gains in filling up the last 4 slots unless your system needs the memory.

Do, however, make sure that your pairs of ram are on different cards. Riser A should have 2 chips and Riser B should also have 2 chips (rather than 4 on one riser)

-Xy

peeb · Apr 14, 2007, 08:19 PM

I have a feeling that tweaking memory performance is not going to solve this - the Pro should be blazing on iTunes whatever is going on.

damiensmunki · Apr 14, 2007, 09:04 PM

I have the stock 512 x 2 plus 1 gig x 2. Coverflow is what bogs it down. With as much music as I have, the RAM gets filled with the cover art. When I load my library, Activity Monitor says iTunes is using around 1.2 gigs. Then I try to work in Aperture, and well...not such a good time. I was thinking that with a faster drive, all the artwork might not need to be stored in RAM. Is this a pipedream? What, exactly, would speed up with the faster drive? Thanks!
Rob

svtcontour · Apr 14, 2007, 09:13 PM

Not sure if this is relevant as I dont have a Mac anymore but I have had tons of experience building machines on the PC side and I can say one thing I've noticed.... nothing and I say NOTHING makes as much of an impact IMO as a fast hard drive. Yes RAM is great but past a certain amount, the benefits diminish but stuff always gets read and written to the HD and thats the slowest device in a computer by far so speeding that up is really important.

I currently have some 15K SCSI drives in my box and I'd easily go from a Core 2 DUO CPU down to a single core Pentium 4 3.0Ghz before I sold the 15K drives and went with 7200RPM SATA drives.

My guess is that if you go with the 10K drive, you will find the difference fairly enormous - providing the slowown you're having is truely disc based.

himself · Apr 15, 2007, 01:19 AM

This sounds more like an iTunes issue to me. If performance improves when you're not viewing with coverflow, I would suggest viewing your iTunes library without it. Otherwise, you could try using smaller images for your album artwork. How big is your album art, by the way?

mr. burns · Apr 15, 2007, 01:50 AM

Seems kind of strange to have coverflow going when you're in a full screen image editing app the whole time? Just turn it off and see what happens. If your RAM gets freed up, it's an iTunes problem. If not, it's a hardware issue.

nerd · Apr 15, 2007, 03:26 PM

I'm not trying to derail this thread but since memory was discussed here's my question.

I'm about to order a 2.66 Mac Pro with the stock 1GB RAM. I'm then going to add 4 x 1GB RAM so Ill have 5 GB total. Since I have 4 matching sticks of memory will that part of the memory be fast and only slow down when it reaches the stock 2 512MB chips or will the whole memory system be slow until I add 2 more 512MB chips.

-Brad

mduell · Apr 15, 2007, 04:59 PM

Originally Posted by nerd

I'm not trying to derail this thread but since memory was discussed here's my question.

I'm about to order a 2.66 Mac Pro with the stock 1GB RAM. I'm then going to add 4 x 1GB RAM so Ill have 5 GB total. Since I have 4 matching sticks of memory will that part of the memory be fast and only slow down when it reaches the stock 2 512MB chips or will the whole memory system be slow until I add 2 more 512MB chips.

If you arrange the memory intelligently (bigger modules toward the inside of each card), The 4 1GB modules will be fast and low latency and the 512MB modules will have higher latency.

nerd · Apr 15, 2007, 05:15 PM

Originally Posted by mduell

If you arrange the memory intelligently (bigger modules toward the inside of each card), The 4 1GB modules will be fast and low latency and the 512MB modules will have higher latency.

Cool, so even if I only have 2 512MB modules last on the riser cards I'll be 256-bit wide bus on my first 4GB?

mduell · Apr 15, 2007, 06:23 PM

Originally Posted by nerd

Cool, so even if I only have 2 512MB modules last on the riser cards I'll be 256-bit wide bus on my first 4GB?

Having at least 4 modules (in the right slots) gives you the full bus width.