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Memory for Mac Pro

S

statistical

macrumors newbie
Original poster
Jul 9, 2010
12
0
I'm just getting a Mac Pro single 3.33GHz 6core.

Happy with the drives at the moment although I may add SSD into the free optical and bay 1 when I have the funds (OSX an Win7 Bootcamp). I've a number of drives availabe for the other three bays.

Usage will be Windows under VMWare in various configurations mainly server orientated from a single virtual to a small network, OSX software as and when I've not used much but am getting to like it (I've a Mac Mini at the moment and really like it but I need to get rid of my old PCs). I will be doing some graphics and music work but probably no video, at the moment.

The other use will be gaming using Bootcamp.

It comes with 3GB of memory my options for upgrading are:

2 x 4 + 2 x 1 - 10GB (120 - Crucial)
3 x 4 - 12GB (180 - Crucial)
4 x 4 - 16GB (240 - Crucial)
2 x 8 + 2 x 1 - 18GB (451 - Crucial, 377 Hynix)
3 x 8 - 24GB (677 - Crucial, 543 Hynix)
4 x 8 - 32GB (900 - Crucial)

All prices in UK Pounds.

The details of the memory I have is
DDR3-10600, 1333MHz, 240 pins, ECC, Registered, CL 9-9-9

What I need to know is which is the best option for upgrading, triple channel or dual channel, will I benefit from the memory above 16GB (4x4) and put the money saved towards the SSDs.

Comments appreciated.

TIA
 
buy the 3 x 4gb for 12gbfor today. Then in the summer the 8gb will drop a lot of money. you can always add 3 8gb sticks in aug of 11.

I am thinking 12gb may be more then enough ram for your needs today.
 
I just ordered the 3.33 GHz 6-core to replace my aging 2006 MacPro and I went with the 3 x 4GB RAM for a total of 12 GB from Other World Computing (Macsales.com). Total cost was $225 plus shipping.
 
Does the triple channel vs dual channel (one or two pairs) make that much difference to performance?

TIA
 
you are best off with the maximum ram that you need ie 3 sticks of 4 gb does not do better then 4 sticks of 4 gb if you use 14gb of the ram.

bear with me this needs a long explanation.

1)any time you exceed the ram in the machine you are better off with more ram.

(most of the time this is the most important rule)

2) pairs of eight give you 16 gb.
if you have a program that eats ram but only wants 2 cores of cpu. BTW I don't know of this program but it could exist, then pairs of 8 would work better then three 4's and an eight even though this is 20 gb of ram this is a case that rules out the top rule

3) triple of the same is better. it is much the best setup if you never exceed the triple.


this is why I said buy 3 sticks of 4gb. if you use 2 gb to 9 gb of ram this would be fastest

4) try and save some money don't rush buying ram see if 3 gb is enough most likely it is not.

5) if you are usa here is a 4gb link of the same ram i use
the link below is dead.

https://www.superbiiz.com/

i have 3 sticks at 41.49 each at that price buying a fourth is not going to kill you. some sellers want 100 a stick apple wants more!
 
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Just a note: Your prices for crucial 4GB DIMMs indicate to me that they are unbuffered ECC, the same as the 3x1GB that comes with the system. These should mix fine, but mixing in 8GB DIMMs that are Registered ECC is not possible.
 
Thanks for that I hadn't noticed.

I probably wouldn't have mixed the 1GB with any other as I tend to keep all my memory the same, but if I hadn't mentioned the option I'm sure someone else would have done.
 
A lot of people here at MR always suggest either OWC or Crucial brand memory. Being a cheapass, I bought 2GB RAM (512MB x 4) on Ebay from a no-name brand memory company and I've never had a problem with heat or performance. It was actually incredibly cheap- ended up paying something like $24 for the lot of it. I now have 5GB RAM total, all of the memory slots filled.
 
I have exactly the same problem -

Hi

Also just taken delivery of a 3.33 6-core Westmere Pro and need to increase the memory to 12 or 16gb (it came via Apple Refurb with only 3gb).

From the responses I'm still unclear wether I'll get better performance from 3 or 4 4gb cards.

It seems counter-intuitive to go for 12gb rather than 16, however, I've heard that three cards will work better than four but I've also heard that matched pairs are generally better than odd numbers and that seems contradictory.

Could someone explain to me in simple terms what's the optimum memory solution for this machine!

PS. I'm in the UK and would prefer to buy here - anyone care to recommend a supplier of really good memory in the UK - it's expensive over here and I only want to buy it once.

TIA

d.
 
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Crucial sell a kit of 3x4Gb for the 6-core at £180 plus UK shipping. It is ECC but unregistered.

Scan.co.uk sell a 3x4Gb Hynix kit for £260 which is "server" memory ECC and registered.

I understand from my reading today that Westmere has a few tricks up its sleeves if it is given registered memory but provided what you buy is ECC, registered or not doesn't matter (with the proviso that you can't mix registered and unregistered).
 
Hi

Thanks for that, I also heard that Westmere's are picky about memory. The Hynix sounds good. Do I take it that the optimum is fitting three rather than four cards? As I said, seems counter-intuitive to go for 12GB rather than 16.

Best wishes,

d.

DanielCoffey said:
Crucial sell a kit of 3x4Gb for the 6-core at £180 plus UK shipping. It is ECC but unregistered.

Scan.co.uk sell a 3x4Gb Hynix kit for £260 which is "server" memory ECC and registered.

I understand from my reading today that Westmere has a few tricks up its sleeves if it is given registered memory but provided what you buy is ECC, registered or not doesn't matter (with the proviso that you can't mix registered and unregistered).
Click to expand...
 
I think the 4th slot is shared with the third one so while it will happily take 16Gb, there will be some slight slowdown. I am not certain of the details - you would have to ask someone other than me.

I ordered the Hynix ECC registered kit by the way - should arrive next week and I added the Scan accidental damage insurance because I know RAM is sensitive.

Oh, and before you worry, yes, both the Hynix and Crucial ram have the inbuilt temp sensors the Mac Pro needs.
 
Thank you, that's all I need. I'll call them tomorrow.

Best wishes,

d.

DanielCoffey said:
I think the 4th slot is shared with the third one so while it will happily take 16Gb, there will be some slight slowdown. I am not certain of the details - you would have to ask someone other than me.

I ordered the Hynix ECC registered kit by the way - should arrive next week and I added the Scan accidental damage insurance because I know RAM is sensitive.

Oh, and before you worry, yes, both the Hynix and Crucial ram have the inbuilt temp sensors the Mac Pro needs.
Click to expand...
 
DanielCoffey said:
Crucial sell a kit of 3x4Gb for the 6-core at £180 plus UK shipping. It is ECC but unregistered.

Scan.co.uk sell a 3x4Gb Hynix kit for £260 which is "server" memory ECC and registered.

I understand from my reading today that Westmere has a few tricks up its sleeves if it is given registered memory but provided what you buy is ECC, registered or not doesn't matter (with the proviso that you can't mix registered and unregistered).
Click to expand...

Apple only support unbuffered ECC memory for the Mac Pro. Registered ECC works with it though. A single UDIMM in each channel is the fastest memory configuration.

Registered memory is faster when placing more than one DIMM on a channel, i.e filling the Mac Pro's 4 or 8 memory slots. We aren't talking huge performance differences though.

Ideally you should buy UDIMMs unless RDIMMs are cheaper. The real exception is if you want to use 8GB DIMMs, which until now are only available as RDIMMs.

So you might want to cancel your order from scan. That £80 extra offers nothing to you and reduces the performance by ~1% over unbuffered DIMMs. The cheapest kit is probably Kingston's KVR1333D3E9SK3/12G
 
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Thanks, not necessarily looking for the cheapest, just the right solution - a compromise, as ever. Looks like I'll be making several calls tomorrow...

Best,

d.

Umbongo said:
Apple only support unbuffered ECC memory for the Mac Pro... Ideally you should buy UDIMMs unless RDIMMs are cheaper. The cheapest kit is probably Kingston's KVR1333D3E9SK3/12G
Click to expand...
 
Called several dealers here in the UK, the C/S at Crucial were pleasant but not very knowledgeble - didn't inspire confidence. No sale.

Spoke with Orca Logic Ltd, lots of questions. They called me back and gave me chapter and verse. I bought 3x4GB Modules mfd by Trancend. Total cost (inc next-day delivery) GBP 154.89 plus VAT. No problems. Transformed performance. Happy.

Nice people, highly recommended. www.orcalogic.co.uk

d.


Diseca said:
Thanks, not necessarily looking for the cheapest, just the right solution - a compromise, as ever. Looks like I'll be making several calls tomorrow...

Best,

d.
Click to expand...
 
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