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Specs for a new Mac Pro

Mitchell

New member
I'm hoping to get this thing ordered today, and I think I've mostly settled on what I'm going to get, but Stuart's post gives me pause.

Will a 4 Core 2.96 with 8 gig mem. run LR and PS faster than a 8 Core 2.26 with 12 gig mem., all other things (drives,etc.) being equal, at considerably less expense?

I buy the future proofing argument so am leaning towards 8 core, but would only consider an 2.26 8 Core because of the big dollar jump for faster 8 core speeds.

Thanks for all the great expertise on this thread.

Mitchell
 

Guy Mancuso

Administrator, Instructor
I would go for the cores even though PS may not fully use them. At some point Snow Leopard and CS5 will come along and it may very well be heavily core dependent. Ram , Hard Drives and all that can be upgraded anytime . Processors and cores cannot. Jack can give you maybe a better answer on the speed with 4 vs 8 but I know my 4 core could not keep up with his new 8 core although I was very close with 10k drives and 12gb of Ram. Also these new processors out are different than before . For a good read visit Lloyds site also. Good friend of GetDPI and very knowledgeable http://macperformanceguide.com/
 

jonoslack

Active member
Jono, are you sure the iMac has the 5400 rpm drive and the MacBook has the 7200 drive? It has been a long time since 3.5" SATA drives were 5400 RPM unless you specifically bought one, and MacBooks still come with 2.5" 5400's. Your numbers would make perfect sense if the 7200 drive was in the iMac and the 5400 in the MacBook, because drive size and spin speed have significant impact on overall performance...
Hi Jack
Actually, I'm not certain about the IMAC - so that could be 7200 as well
I AM certain about the MBP though as I fitted the 7200 300gb drive myself!

Honest Jack - the difference is stunningly obvious.
 

carstenw

Active member
Yup, if the 8GB don't work, that's what I'll have to do.

I forgot to mention: although the speed of the drive in my MacBook Pro 15" is 7200rpm, that doesn't mean that the drive is as fast as a 3.5" desktop drive. The seek times and latencies are much better on desktop drives, so the laptop will still be slower.
 

Guy Mancuso

Administrator, Instructor
Yup, if the 8GB don't work, that's what I'll have to do.

I forgot to mention: although the speed of the drive in my MacBook Pro 15" is 7200rpm, that doesn't mean that the drive is as fast as a 3.5" desktop drive. The seek times and latencies are much better on desktop drives, so the laptop will still be slower.
Yea there is no 32 cache in laptop drives , 16 is the biggest.
 

Mitchell

New member
Guy,

Thanks for your response, and it is the way I'm leaning.

Just wondering about paying alot more money to get alot less processing speed 2.26 versus 2.93?

Do the extra cores and ram make that worth the extra money?

Thanks,

Mitchell
 

Guy Mancuso

Administrator, Instructor
Right now Ram is the key with PS and LR and in any box i think 6gb is the minimum. I have seen more performance jump going from 4gb to 6gb in any box I have had. I would suggest that at least that be a starting spot. This gives the system 3gb after PS to work with and PS to tap into those extra 3gb than scratch is also very important for PS. I think anyone will tell you the processing speed jumps are not as relevant as the numbers sound. I think and Jack or Lloyd could confirm this better but from the same family of logic boards the jump from 2.26 to 2.9 maybe yields 10 percent increase. My numbers maybe off here but not as much as we would want to think.

I think barefeats did a test where the 4 core actually beat the 8 core so we have to be careful here . Read this test pretty revealing http://www.barefeats.com/nehal08.html
 

Guy Mancuso

Administrator, Instructor
What is interesting in that test programs that are Ram hungry the 4 core won the race but programs that are core hungry beat the 4 core. As the article warns and we have touched on here is what applications you are using is maybe more the key to the decision process.

For someone like me that uses C1 cores are better but LR users it will be more Ram friendly and as I mentioned early my new laptop with 2 cores matches my old MacPro 4 core and actually it beats it. I think the main reason is better DD3 ram 1056 mhz bigger L2 cache plus very fast SSD drives even though I have less ram in the laptop. Talk about confusing. LOL But in C1 the old box is much faster with the 4 cores.
 

Mitchell

New member
Thanks Guy for the link and your thoughts.

The Barefeats test is pretty amazing because it's comparing 4 Core versus 8 Core with both machines having 12 gig mem. and same 2.93 Processor speed with the 4 Core being slightly faster in Photoshop.

That's about a $3000 pricier machine being slightly slower!

I would guess the 8 Core 2.26 version I was thinking of would be significantly slower than the cheaper 4 Core 2.93.

So the only advantage 8 Core for Photoshop (and I presume LightRoom) lie possibly in the future.

But, LightRoom is now 64 bit. Is Photoshop? Does this mean 8 Core can benefit LightRoom more than Photoshop?

I really appreciate the help on this thread.


Mitchell
 

Guy Mancuso

Administrator, Instructor
Yes the future of 8 core and PS is the future so keep that in mind . Right now it makes very little use after one core. LR I am not sure on 64 bit and have not used it for awhile but I think our system only addresses 32 anyway.
 

carstenw

Active member
Photoshop is not yet fully 64-bit. I believe that will come for Snow Leopard. In effect here, you are gambling on the speed of the 8-core in the future, at a cost today. Personally, I would strongly consider if the 4-core isn't enough. It is still a fast machine, although it doesn't take as much memory in the end. If you plan to use the same back for a few years (3-4?), then the 4-core might be a better bet, and the money saved can be used to buy the next system sooner. OR you bet that everything comes together next year with CS5, Snow Leopard and C1-8-core :)
 

Guy Mancuso

Administrator, Instructor
Sounds like the stock market and hedging our bets. LOL

Snow Leopard rumor is September. CS5 there are no rumors at all and c1 I caught some wind on but my bet a way's out
 

Jack

Sr. Administrator
Staff member
Drives:

1a) The fastest part of a spinning drive is the outer rim. A 3.5" drive spinning at 7200 RPM is going to be faster than a 2.5" drive of the same capacity, spinning at the same speed and at the outer rim of the drive platter, because the outer rim circumference is greater and thus more linear material passing by the head over the same period of time. Once the head on the 3.5" drive sweeps in half way, it is essentially equaling the 2.5" drive at its fastest point.

1b) A larger capacity drive has higher density platters, so for any given speed they will generally be faster than a comparable lower capacity drive for the same reason as above; more material is passing by the head even though it's at the same rotational speed.

1c) Cache size can have a small impact on performance, but usually only helps on large file sustained reads or writes.

Macs:

2a) The new 4-core Mac Pro is limited to 4 RAM slots instead of 8, and will be limited to future software improvements that utilize more cores AND more RAM. Whether that's going to be a significant limitation, only you can answer for yourself based on your planned uses.

2b) I have never met anybody who wished they had bought a slower computer.
 

Mitchell

New member
Thanks Carsten, Guy, and Jack.

LightRoom is 64 bit now, but I haven't seen anything on how it runs 4 Core versus 8 Core.

Jack, Totally agree I want the fastest machine for the buck. Just can't tell which that is: 4 Core 2.93, or 8 Core 2.26, now and in the future. !:^)

Mitchell
 

carstenw

Active member
Okay, but the money has to make sense too. If you load up a big Mac with lots of RAM and processors, you can easily double the price of the entry-level system. The question then is at what point will that big Mac actually be faster with the apps we use? No one knows, but if it takes longer than perhaps two years, then it might be as cheap and faster to get an entry-level now, and another in two years. That second system could easily be faster than the fast system of today.

In the end it is all gambling, as long as the performance isn't there today with the apps we use. In this economy, I would choose the Mac Pro entry machine with 6GB and a couple of big fast drives, and load it up with time, switching to a new system in perhaps 3 years, selling the old.
 

Guy Mancuso

Administrator, Instructor
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