16GB LIMIT for 4-core and 6-core Mac Pro? 32GB limit for 8/12-core Mac Pro?

2010-08-09 • SEND FEEDBACK |
Related: Mac Pro, memory

New 4-core and 6-core Mac Pros might (!) have hard 16GB max memory limit. Discussion below not yet updated for that issue.

Also (!!!) do NOT assume that the 8/12-core Mac Pro will take 8GB modules (they probably will, but there is a non-zero chance they might not).

Until the new Mac Pro ships and can be tested for compatibility, the most you can safely assume is 16GB for the 4/6-core models and 32GB for the 8/12-core models, using 4GB modules. Do not make a purchase decision (yet) assuming otherwise.

Today, I discussed memory for the new Mac Pro today with OWC. From what I understand, it appears that 8GB modules might not work in the new 2010 4/6-core Mac Pro, and there is a (small) chance they might not work in the 8/12-core Mac Pro.

Since 4 X 4GB = 16GB, it appears that 16GB memory might be a hard limit for the new 2010 Mac Pro. This is not yet confirmed and won’t be until OWC gets the new Mac Pros in house (Apple site is stating “7-10 days” for delivery).

As this is a major limitation for big jobs (a non-starter for me), I advise anyone doing big jobs to hold off on the 4 and 6 core models until this becomes clear, at least if you do big jobs on your Mac Pro. Or to get the previous Nehalem, which can take 32GB (I have 24GB in my 3.33Ghz quad-core).

*** The discussion below has not been updated in light of this news ****

*** The discussion below has not been updated in light of this news ****

*** The discussion below has not been updated in light of this news ****

Let me put it this way: 80% of my consulting clients have been delighted with 2.66GHz quad-core Mac Pro Nehalem (2009). The new models do not change that in any appreciable way.

If you want a deal right now, get this 2.66GHz Mac Pro at B&H Photo while they last. The new models won’t show up refurbished for quite some time, so this is the way to go if you’re on a tight budget.

Very little in Apple’s new lineup looks exciting— no major speed bump anywhere. Sure, you can get a 6-core Mac Pro at 3.33GHz instead of 4-cores— worthwhile, but not worth upgrading for unless you spend a lot of time with software that actually uses 6 cores for more than brief blips.

There aren’t some minor improvements in value:

• You can now get a 4-core Nehalem at 3.2GHz for a $400 upcharge (it was a $1300 upcharge for 3.33Ghz before). Slightly slower, a lot less money.
• The 2.8GHz 4-core Nehalem is a smidgen faster at the same price as the former 2.66GHz model. Yawn.
• The 3.33Ghz 6-core offers better top-end performance for users of certain software, such as PhaseOne CaptureOne, and (maybe) Lightroom 3.
• The 8-core 2.4GHz model is a dud. Avoid it unless you really know why you want it. Even so, it seems totally pointless compared to the 3.33Ghz 6-core model.
• The 12-core models are going to be slower than the 3.33Ghz 6-core model for most everything. Only if those cores get used will they matter: certain tasks only, the rest of the time they sit idle. Apple should have offered a 12-core at 3.33Ghz, but didn't.

If you are doing specialized stuff that can max-out 12-cores, you’re going to like the new 12-c0re machines. If not stick to the 4-core or 6-core models.

If you like this site, now is the time to support it: use one of my links to your Mac Pro, thank you!

Single-processor configurations

The 6-core 3.33GHz model is the “sweet spot” — for most tasks it should prove to be the fastest of all the models, including the 12-core ones.

Dual-processor configurations

The 8-core is a dud. Spend your money on the 6-core 3.33Ghz model instead, unless you must have 8 memory slots.

Forget about 12 cores unless you actually have tasks(s) that benefit. Or you need 8 memory slots 24GB or 48GB or 64GB memory, for really big jobs.

It’s too bad that Apple chose to not offer a 12-core model at 3.33Ghz, which has a 13% faster clock speed than the 2.93GHz model. Intel has a 3.47GHz chip in the works also.