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bzollinger
Aug 10, 2010, 02:32 PM
Just a quick question about the four RAM slots in the SP 2010 MPs. If an MP was ordered with 3GB of RAM, and an 8GB (2x4GB) kit was purchased, could you simply pull one of the 1GB DIMMS, and add the two 4GB sticks to make a total of 10GB of RAM?

Would that mean the the DIMMS would operate in dual channel mode? And would the 4GB sticks need to be installed in the first two RAM slots with the 1GB sticks in the 3rd and 4th slots?

Thanks,
BZ



keewe
Aug 10, 2010, 03:21 PM
u cant use RAM from other vendors like OWC with the shipped apple ram.

Spanky Deluxe
Aug 10, 2010, 03:25 PM
u cant use RAM from other vendors like OWC with the shipped apple ram.

Incorrect.

Just a quick question about the four RAM slots in the SP 2010 MPs. If an MP was ordered with 3GB of RAM, and an 8GB (2x4GB) kit was purchased, could you simply pull one of the 1GB DIMMS, and add the two 4GB sticks to make a total of 10GB of RAM?

Would that mean the the DIMMS would operate in dual channel mode? And would the 4GB sticks need to be installed in the first two RAM slots with the 1GB sticks in the 3rd and 4th slots?

Thanks,
BZ

Yes that's exactly how it would work. It would run with 2x1GB and 2x4GB in dual channel giving 10GB total in dual channel mode.

keewe
Aug 10, 2010, 03:37 PM
did they change anything with the 2010 line or is OWC just missing the info on their 2010 page?

IMPORTANT OWC NOTE:

The OWC p/n OWC8566D3MPE4GB 4GB modules included in this kit require that all installed modules be of this same matching part. Other existing Apple or 3rd party 1GB, 2GB and 4GB modules are not supported for use with this kit and need to be removed when this kit is added.

http://eshop.macsales.com/item/Other%20World%20Computing/85MP3S4M12GK/

strausd
Aug 10, 2010, 04:00 PM
did they change anything with the 2010 line or is OWC just missing the info on their 2010 page?



http://eshop.macsales.com/item/Other%20World%20Computing/85MP3S4M12GK/

I noticed that and thought it was strange. Maybe they haven't said it yet because they haven't been able to test it yet.

bzollinger
Aug 10, 2010, 04:12 PM
That would be strange if it didn't work. As long as the RAM is of the same spec it shouldn't matter from what I understand. I'd also be probably buying it from these guys anyway: http://www.transintl.com/store/category.cfm?Category=2859&RequestTimeOut=500

They have a lifetime warranty and as long as the pairs are from one company, in this case one pair of 1GBs from Apple and a pair of 4GBs from transintl.com I should be good to go.

That's a good deal too if you ask me. Add $285 to the $2659 (education price), and get a 3.2GHz Quad w/ 10GB of RAM for $2944 just under $3k. Right at budget!

If I bump up to the 3.33 GHz hexacore then I'm over budget and not real sure that I'll benefit from it with my work flow.

Thanks for the info.

Icaras
Aug 10, 2010, 04:25 PM
Incorrect.

Would you mind elaborating for us? A few of us here, including myself, were under the impression that you could not mix RAM modules by various vendors, and I think we took OWC's warning literally.

From the OWC page of the module that keewe just linked:

The OWC p/n OWC8566D3MPE4GB 4GB modules included in this kit require that all installed modules be of this same matching part. Other existing Apple or 3rd party 1GB, 2GB and 4GB modules are not supported for use with this kit and need to be removed when this kit is added.

I also remember researching this and found a thread under the Apple support discussions that some people had problems going this route.

So is this just marketing gimmick by OWC to get us to buy all their RAM from them. Honestly, I find it wierd myself that you wouldn't be able to mix and match various vendor RAM, and that was the first time I've heard of such a warning, so I wanted to clear this up for good.

strausd
Aug 10, 2010, 04:27 PM
That would be strange if it didn't work. As long as the RAM is of the same spec it shouldn't matter from what I understand. I'd also be probably buying it from these guys anyway: http://www.transintl.com/store/category.cfm?Category=2859&RequestTimeOut=500

They have a lifetime warranty and as long as the pairs are from one company, in this case one pair of 1GBs from Apple and a pair of 4GBs from transintl.com I should be good to go.

That's a good deal too if you ask me. Add $285 to the $2659 (education price), and get a 3.2GHz Quad w/ 10GB of RAM for $2944 just under $3k. Right at budget!

If I bump up to the 3.33 GHz hexacore then I'm over budget and not real sure that I'll benefit from it with my work flow.

Thanks for the info.

Just FYI OWC has the same warranty. And I think TransIntl also has the same disclaimer about only using matching pairs. And if the 1GB sticks won't work with the 4GB sticks at the same time, you can't send them to TransIntl for a rebate, but you can with OWC. But as far as I know, both companies have good quality RAM. Crucial is supposed to as well, but their prices have gone way up lately.

Edit: From TransIntl:
"Note: 4GB Modules should be matching pairs from Transintl only."

bzollinger
Aug 10, 2010, 04:33 PM
Here's my effort to clear this up.

You can run memory in dual or tripple channel modes. If you're running in tripple channel you must have a "kit" from whomever of 3 matching DIMMS. You can't put one Apple DIMM and two OWC DIMMS and make a tripple channel kit. This has been the case for matching pairs (two DIMMS) and for tripple channel memory since dual channel memory came out.

So in my scenerio, I want to run the memory in dual channel mode with two kits. One "kit" will be two 1GB sticks from Apple (bought w/ MP), and one "kit" of 4GB sticks from transintl or OWC. Both PAIRS will run in dual channel mode and should be compatible with each other.

Apple is stupid for touting the SP MPs w/ four RAM slots as tripple channel, it doesn't add up very well, as you can max it out w/ 3x4GB chips and have one unused slot.?????:confused::rolleyes:

Make sense?

nanofrog
Aug 10, 2010, 06:45 PM
Edit: From TransIntl:
"Note: 4GB Modules should be matching pairs from Transintl only."
The 4GB DIMM's have a thermal sensor on them.

There's other caveats too (Intel, not Apple), such as it all must be the same type (non-ECC, and if it's ECC, it all has to be either UDIMM or RDIMM; Unbuffered and Registered ECC respectively). These different types of DDR3 cannot be mixed together.

Icaras
Aug 10, 2010, 06:51 PM
The 4GB DIMM's have a thermal sensor on them.

There's other caveats too (Intel, not Apple), such as it all must be the same type (non-ECC, and if it's ECC, it all has to be either UDIMM or RDIMM; Unbuffered and Registered ECC respectively). These different types of DDR3 cannot be mixed together.

So it simply because there are so many variables to consider that these vendors go out of their way to claim that all modules should be purchased by them and not mixed with others?

So that they can avoid confused and angry customers when there MP gets bricked from mixing different types of DIMMs?

keewe
Aug 10, 2010, 06:54 PM
thats interesting. so its possible it works out fine? and you can't do any damage by just give it a shot?

nanofrog
Aug 10, 2010, 07:09 PM
So it simply because there are so many variables to consider that these vendors go out of their way to claim that all modules should be purchased by them and not mixed with others?

So that they can avoid confused and angry customers when there MP gets bricked from mixing different types of DIMMs?
Sort of.

You can mix 1 & 2GB OEM and OWC or TransInt'l DIMMs (all UDIMM without any thermal sensors). The 4GB sticks have the thermal sensors, and don't work properly if mixed with UDIMM's missing the sensor (so 4GB UDIMM won't play well with smaller UDIMM's, as they're missing the blasted sensor).

The 8GB sticks also have the thermal sensors, but though not stated, it's RDIMM, which is why it won't mix with the smaller capacity DIMM's either.

So OWC tried to make it easier, and make the statements they do. ;)

Icaras
Aug 10, 2010, 07:22 PM
Sort of.

You can mix 1 & 2GB OEM and OWC or TransInt'l DIMMs (all UDIMM without any thermal sensors). The 4GB sticks have the thermal sensors, and don't work properly if mixed with UDIMM's missing the sensor (so 4GB UDIMM won't play well with smaller UDIMM's, as they're missing the blasted sensor).

The 8GB sticks also have the thermal sensors, but though not stated, it's RDIMM, which is why it won't mix with the smaller capacity DIMM's either.

So OWC tried to make it easier, and make the statements they do. ;)

I see. Yea they definitely do simplify the reason :)

So starting from 4GB DIMMs and up, they have that thermal sensor, and so really, I can order OWC and mix it with my stock 3x1GB Apple DIMMs without any hitch then?

But do DIMM sizes have to match in size? For example, I can't leave 2x1GBs of Apple RAM inside and plug the third DIMM slot with a 1x4GB DIMM from OWC. They would either have to be all 1GB DIMMs or 4GB DIMMs?

I hope I have this right....

Edit: Sorry, got it. Just read "matched sets required". Thanks!

PMacP
Aug 10, 2010, 07:35 PM
So in my scenerio, I want to run the memory in dual channel mode with two kits. One "kit" will be two 1GB sticks from Apple (bought w/ MP), and one "kit" of 4GB sticks from transintl or OWC. Both PAIRS will run in dual channel mode and should be compatible with each other.

Then, would this scenario also work for triple channel mode:
3x1GB from Apple + 3x4GB from OWC?

CaoCao
Aug 10, 2010, 07:46 PM
Then, would this scenario also work for triple channel mode:
3x1GB from Apple + 3x4GB from OWC?

yes, but it would have to be the right slots provided the OWC ones are ECC and of the right kind of ECC

bzollinger
Aug 10, 2010, 08:03 PM
yes, but it would have to be the right slots provided the OWC ones are ECC and of the right kind of ECC

No, in the case of the 4 or 6 core machines because there are only four slots, but yes in the case of the 8 or 12 core machines because there are enough slots, but as you say, they have to be in the proper slots.

Spanky Deluxe
Aug 10, 2010, 09:08 PM
Wow, I didn't know about the thermal sensor in the 4GB modules at all. I don't understand why if one pair has a thermal sensor then it means another separate pair without the sensor will make things mess up. I thought all that mattered were matched pairs. Apple doesn't say anything on their Mac Pro memory page (http://store.apple.com/us/memorymodel/ME_MACPRO_S10_RAM) or the Mac Pro tech specs page (http://www.apple.com/macpro/specs.html). Maybe Apple's 4GB DIMMs don't have the thermal sensor on them.

Sleephartha
Aug 10, 2010, 09:32 PM
Can someone post a good link that will explain RAM configurations clearly and simply? This must exist somewhere. Or just spell it out here? I've searched a few sites online and still don't think I have a clear picture. There seem to be quite a few variables:

Single vs Dual Processor
Dual/Triple Channel
Pairs vs Triads
What slots to put them in
Mixing sizes (1/2/4/8 gig)
"Kits" (Is it just a 'set' of 2 for dual and 3 for triple?)

I had assumed that for my Quad 3.2 the goal would eventually be to max out the ram at 16g so that the sensible thing to do would be to buy 2x4g sticks so that I could eventually add 1 or 2 more 4g sticks if necessary. But would 3x4g sticks run triple channel and 4x4g run in dual channel? Ugh. Clarity....

***Edit*** Just found this link which has been helpful:

http://macperformanceguide.com/Reviews-MacProWestmere-Memory.html

skiffx
Aug 10, 2010, 11:18 PM
Isnt it always recommended to have the same type of ram in all slots? In PCs I always thought that you wouldnt want to mix 4gb sticks with 1gbs even if they are properly channeled.

PMacP
Aug 11, 2010, 12:06 AM
No, in the case of the 4 or 6 core machines because there are only four slots, but yes in the case of the 8 or 12 core machines because there are enough slots, but as you say, they have to be in the proper slots.

Thanks for the replies.

In a 12-core scenario with 3x1GB from Apple and 3x4GB from OWC, what are the proper slots? Apple 1, 2, 3 and OWC 4, 5, 6 - meaning they'd have to be sequential?

gaspra
Aug 11, 2010, 03:32 AM
Can someone post a good link that will explain RAM configurations clearly and simply?


When I installed the 3party ram in my 2009, after reboot the OS asked me to change the ram sequence. There was a on screen diagram showing the configuration. I had 6x1GB and I added 2x2GB, so the configuration was:

slot 1(5): 1GB
slot 2(6): 2GB
slot 3(7): 1GB
slot 4(8): 1GB

gaspra
Aug 11, 2010, 03:34 AM
Would you mind elaborating for us? A few of us here, including myself, were under the impression that you could not mix RAM modules by various vendors, and I think we took OWC's warning literally.


Because OWC warned people doesn't mean you can't use other rams. I am using Patriot 4GB Mac compatible memory, works like a charm. The OS has no problem showing the ram info including the serial numbers.

cutterman
Aug 11, 2010, 08:45 AM
The temp sensors are available on 1 and 2gb 1333mhz dims, not just the 4 gb modules. These were Kingston parts on ramshopping.com.

I ordered additional 4gb dims from crucial for a 12 core system. Hopefully they will be compatible with the existing 2gb units. I am waiting to hear from crucial on the compatibility question. I would be surprised if they are not.

bzollinger
Aug 11, 2010, 12:53 PM
I'm pretty sure that as long as the memory is of compatible spec in regards to, dual or triple channel kits (matched DIMMS), ECC, proper speed (1066 or 1333MHz), and installed in the proper slots it will work.

As gaspra states if you get the order wrong the MP is smart enough to know, and will guide you to the proper placement.

Also I'm pretty sure that if you use 1333MHz memory in a system that runs at 1066MHz, it will simply throttle it back to 1066MHz. So really if the price is the same why not buy the faster RAM?

nanofrog
Aug 12, 2010, 12:14 AM
The temp sensors are available on 1 and 2gb 1333mhz dims, not just the 4 gb modules. These were Kingston parts on ramshopping.com.
Yes, but they're not required (Intel's design, as the smaller DIMM's wouldn't get hot enough to need them). But mixing them with non-thermal sensored DIMMs would cause problems.

Also I'm pretty sure that if you use 1333MHz memory in a system that runs at 1066MHz, it will simply throttle it back to 1066MHz.
Yes. It would just function at 1066 if that's all that the memory controller was designed for (max mem frequency), or as the 2009 systems are currently, limited by the firmware (i.e. a couple of 1333 compliant CPU's came out, 3.2 and 3.33GHz SP Quads, but still run at 1066 as a result).

bzollinger
Aug 21, 2010, 01:31 PM
I'm bumping this back up to the top to see if anyone has any new insight about tripple, dual, single channel memory operation.

Will the 3.2GHz quad run in dual channel mode with two 1GB DIMMS from apple and two 4GB DIMMS from transintl? Each pair should be "matched" so I'm really hoping I don't get knocked down to single channel mode.....

lucidmedia
Aug 21, 2010, 09:49 PM
I received an email last night from a OWC tech that confirmed that 2x4GB + 2x1gb (apple) ram does indeed work.

Novablas
Aug 21, 2010, 10:55 PM
I received an email last night from a OWC tech that confirmed that 2x4GB + 2x1gb (apple) ram does indeed work.

But 2x 4GB + 3x1gb (apple) ram would not work?

If it has to be pairs then why does 3x1gb work?

or 3x any size?

Icaras
Aug 21, 2010, 11:06 PM
But 2x 4GB + 3x1gb (apple) ram would not work?

Because 2 + 3 = 5.

The quad/hex only has 4 RAM slots.

If it has to be pairs then why does 3x1gb work?

or 3x any size?

Because you're using the DIMMS in triple channel, which is what the Nehalem/Westmere architecture seems to be designed and optimized for. There are a ton of RAM threads going about right now that go more into detail about this.

Novablas
Aug 21, 2010, 11:11 PM
Because 2 + 3 = 5.

The quad/hex only has 4 RAM slots.



Because you're using the DIMMS in triple channel, which is what the Nehalem/Westmere architecture seems to be designed and optimized for. There are a ton of RAM threads going about right now that go more into detail about this.

Ah I see, thanks. And I just assumed the Quads/Hexs had more ram slots because my 2006 Mac Pro does. Forgot about them being a single processor.

Wait so do 8GB sticks work in the quads/hexs? If I bought one of those could I then use the 3x1GB that comes default with it for 11gb of ram?

Edit: Oh wait nvm, OWC says their 8GB sticks can only be used with other 8GB sticks.

Icaras
Aug 21, 2010, 11:56 PM
Ah I see, thanks. And I just assumed the Quads/Hexs had more ram slots because my 2006 Mac Pro does. Forgot about them being a single processor.

Wait so do 8GB sticks work in the quads/hexs? If I bought one of those could I then use the 3x1GB that comes default with it for 11gb of ram?

Edit: Oh wait nvm, OWC says their 8GB sticks can only be used with other 8GB sticks.

Yea np, 8GB DIMMS are definitely confirmed. You just have to use all OWC sticks like you mentioned :p

Also, i chatted with an OWC rep last night and he confirmed to me that you cannot use just a single 8 DIMM. You have to start with two DIMMS at the very least.

bzollinger
Aug 22, 2010, 12:10 AM
I received an email last night from a OWC tech that confirmed that 2x4GB + 2x1gb (apple) ram does indeed work.

Awesome!! Thanks for the response. So it works which is great, but did they say anything about dual/single channel mode?

Can anyone confirm this? I can't afford 3x8GB so I'm looking into dual channel mode for the Nehalem procs.

If the two pairs will interleave (dual channel I think) then anyone doing this will be in good shape. Granted it won't be as "fast" as triple channel. I can forego a 2% theoretical increase in speed to get my MP up to 10GB from base for $250:eek:

dolz
Aug 22, 2010, 08:08 AM
The used Mac Pro 1,1 came with 1GB of memory. I added another 8GB bought from OWC. I had no problems at all. In fact today I just added another 1GB of Apple memory that I got on sale from OWC to fill out my risers.

DIMM Riser A/DIMM 1: 2GB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x05F7
DIMM Riser A/DIMM 2: 2GB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x05F7

DIMM Riser B/DIMM 1: 2GB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x05F7
DIMM Riser B/DIMM 2: 2GB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x05F7

DIMM Riser A/DIMM 3: 512MB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x80AD
DIMM Riser A/DIMM 4: 512MB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x80AD

DIMM Riser B/DIMM 3: 512MB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x802C
DIMM Riser B/DIMM 4: 512MB, DDR-2 FB-DIMM, 667 Mhz, Manufacturer 0x802C

bzollinger
Aug 23, 2010, 01:56 PM
I just read this and believe it has finally answered this question. In short the 2010 SP MP 3.2GHz quad should have no problem running 10GB of RAM in dual channel mode. Furthermore the benefits of triple channel memory are negligible. :cool:

http://macperformanceguide.com/Reviews-MacProWestmere-MemoryBandwidth.html

Chenier
Aug 23, 2010, 06:17 PM
Find out for myself today, though others have already confirmed... 3.2 ghz quad core running with 2 x 4gb ram from OWC + 2 x 1gb ram from Apple = 10 gb ram

bzollinger
Aug 23, 2010, 06:36 PM
Find out for myself today, though others have already confirmed... 3.2 ghz quad core running with 2 x 4gb ram from OWC + 2 x 1gb ram from Apple = 10 gb ram

It's great to know that it works. Can you confirm that it's running in dual channel mode?
thanks,
Ben

johnnymg
Aug 23, 2010, 07:01 PM
I'm pretty sure that as long as the memory is of compatible spec in regards to, dual or triple channel kits (matched DIMMS), ECC, proper speed (1066 or 1333MHz), and installed in the proper slots it will work.

As gaspra states if you get the order wrong the MP is smart enough to know, and will guide you to the proper placement.

Also I'm pretty sure that if you use 1333MHz memory in a system that runs at 1066MHz, it will simply throttle it back to 1066MHz. So really if the price is the same why not buy the faster RAM?

FWIW: Diglloyd verified that the hex can be used with 1066 RAM:
http://macperformanceguide.com/Reviews-MacProWestmere-MemoryBandwidth.html

Would be interesting to see if the Hex can handle mixed RAM speed modules. :p.

Chenier
Aug 23, 2010, 07:16 PM
It's great to know that it works. Can you confirm that it's running in dual channel mode?
thanks,
Ben

Pardon my naïveté, but how/where do I check for this?

Fiete5401
Aug 23, 2010, 07:16 PM
Find out for myself today, though others have already confirmed... 3.2 ghz quad core running with 2 x 4gb ram from OWC + 2 x 1gb ram from Apple = 10 gb ram

Hi Chenier!

Could you please run 64-bit Geekbench on your new MP and post your results to the Geekbench database? Your results would help me and others in their buying decision. Thanks!

bzollinger
Aug 23, 2010, 07:30 PM
Pardon my naïveté, but how/where do I check for this?

I'm sorry I don't know how to check for that. I've searched for a way or a utility but haven't found one yet.

Maybe someone else here know....

Chenier
Aug 23, 2010, 07:37 PM
Hi Chenier!

Could you please run 64-bit Geekbench on your new MP and post your results to the Geekbench database? Your results would help me and others in their buying decision. Thanks!

Would love to help, but finances are rather tight after all the upgrades. Is there a free alternative to Geekbench that would satisfy your curiosity?

Fiete5401
Aug 23, 2010, 07:41 PM
I'm sorry I don't know how to check for that. I've searched for a way or a utility but haven't found one yet.

Maybe someone else here know....

Maybe the Memory Configuration Tool (I think it is named like that in english) can help.
You can find it in /System/Library/CoreServices.

Would love to help, but finances are rather tight after all the upgrades. Is there a free alternative to Geekbench that would satisfy your curiosity?

Well, in this case please just run the 32-bit version. As there are no results at all for the 3.2 quad every single bit of information helps.

Chenier
Aug 23, 2010, 08:02 PM
Maybe the Memory Configuration Tool (I think it is named like that in english) can help.
You can find it in /System/Library/CoreServices.

When I run this (Memory Slot Utility) I only get this simple message:
247977

Well, in this case please just run the 32-bit version. As there are no results at all for the 3.2 quad every single bit of information helps.

Done. For what the 32-bit version is worth, the results are here:
http://browse.geekbench.ca/geekbench2/view/281986

Not familiar with these numbers yet; does this sound ok for my machine specs?

bzollinger
Aug 23, 2010, 08:13 PM
When I run this (Memory Slot Utility) I only get this simple message:
247977



Done. For what the 32-bit version is worth, the results are here:
http://browse.geekbench.ca/geekbench2/view/281986

Not familiar with these numbers yet; does this sound ok for my machine specs?

That sounds pretty good to me!! I have only ran the 32-bit version too. My recently retired Dual 2.0 G5 ran ~1800, and my 2.53GHz late 09 Mini ran ~3500.

Does that put it into perspective a little?

I wonder what the 64-bit results would be? Anyone care to speculate?

Fiete5401
Aug 23, 2010, 08:33 PM
I wonder what the 64-bit results would be? Anyone care to speculate?

I calculated that the 64-bit results are normally around 13% higher than the 32-bit results. That would result in an extrapolated score in the range of 11500.
So far I can tell you that the 3.2 quad gives you would you pay for if you just compare the Geekbench results and the price difference to the 2.8 quad. You pay 16.7% more and get 16.6% more performance.
It is interesting to see that the 3.2 quad has the highest Geekbench score per core of all 2010 MPs.
If we just look at "bang for the buck" the 3.33 hex and the 2.66 dodeca are the clear winners.
The 2.93 dodeca is the problem child of the family. You pay 24.5% more than the 2.66 dodeca but you only get a 9.1% higher score.

All results are based on comparisons of 64-bit Geekbench results which are nothing more than synthetic and not real world observations.
These results can't reflect any real world workflows but I think they can give you an insight about what can be done with these machines if the software can utilize all the power that's buried in them.

barefeats
Aug 24, 2010, 07:12 AM
I tested the 3.33GHz 6-core with two different memory configs. Then I ran a 64 bit memory stress test.

4x8G = 32G = 10.5 GB/s
3x8G = 24G = 14.3 GB/s (or 36% faster)

However, when I ran After Effects CS5 project render using 12 cores and 1.5G per core, the 32G config took 72 sec, the 24G took 71 sec. In other words, if there is a difference in real world performance, you would need a stopwatch to detect it.

Why? Because few if any real world apps use the full memory bandwidth. I'm still testing. If I find any app that benefits from the 3 stick config, I'll report it here.

Fiete5401
Aug 24, 2010, 07:55 AM
Because few if any real world apps use the full memory bandwidth. I'm still testing. If I find any app that benefits from the 3 stick config, I'll report it here.

It's curious to see that most people don't realize that fact. Thanks for your efforts.

bzollinger
Aug 24, 2010, 10:29 AM
I tested the 3.33GHz 6-core with two different memory configs. Then I ran a 64 bit memory stress test.

4x8G = 32G = 10.5 GB/s
3x8G = 24G = 14.3 GB/s (or 36% faster)

However, when I ran After Effects CS5 project render using 12 cores and 1.5G per core, the 32G config took 72 sec, the 24G took 71 sec. In other words, if there is a difference in real world performance, you would need a stopwatch to detect it.

Why? Because few if any real world apps use the full memory bandwidth. I'm still testing. If I find any app that benefits from the 3 stick config, I'll report it here.

Thanks for the info. That is an interesting test for sure.

lucidmedia
Aug 24, 2010, 11:00 AM
I calculated that the 64-bit results are normally around 13% higher than the 32-bit results. That would result in an extrapolated score in the range of 11500.
So far I can tell you that the 3.2 quad gives you would you pay for if you just compare the Geekbench results and the price difference to the 2.8 quad. You pay 16.7% more and get 16.6% more performance.
It is interesting to see that the 3.2 quad has the highest Geekbench score per core of all 2010 MPs.
If we just look at "bang for the buck" the 3.33 hex and the 2.66 dodeca are the clear winners.
The 2.93 dodeca is the problem child of the family. You pay 24.5% more than the 2.66 dodeca but you only get a 9.1% higher score.

All results are based on comparisons of 64-bit Geekbench results which are nothing more than synthetic and not real world observations.
These results can't reflect any real world workflows but I think they can give you an insight about what can be done with these machines if the software can utilize all the power that's buried in them.

My 3.33 hexacore with 10GB ram (4x2, 1x2) got a 16135 in geekbench 64 bit... Its posted in the the results browser.

strausd
Aug 24, 2010, 11:07 AM
I got a 12-core with 20GB RAM. Have 4X4GB (OWC) and 4X1GB (Apple) and everything seems to be working fine. I will try and upgrade to 24GB soon, that way AE will be able to use all cores.

bzollinger
Aug 24, 2010, 11:09 AM
My 3.33 hexacore with 10GB ram (4x2, 1x2) got a 16135 in geekbench 64 bit... Its posted in the the results browser.

That's a great score! But we're talking about the 3.2GHz quad scores because there hasn't seem to be very many of them posted....

strausd
Aug 24, 2010, 11:11 AM
That's a great score! But we're talking about the 3.2GHz quad scores because there hasn't seem to be very many of them posted....

http://www.barefeats.com/wst10.html

Edit: Never mind, that doesn't show 3.2 quad :/