| As I mentioned yesterday I wrote a Micron (Crucial) contact to ask about why they removed their standard (flat heatsink) FB-Dimms from the Mac Pro compatible listing. (I.E. Were they going to offer them later and were they pulled due to their own tests or due to Apple's heatsink notes.) Here's the reply:
"
Hi Mike,
We've been experiencing an inconsistency with the current heat spreaders
on our Mac 1GB FB-DIMM modules after extended use. We're currently
working on a redesign of our heat shield due to these thermal issues and
will be releasing a revised part at a later point in time.
As you can imagine, we've been working closely with Apple and value our
good relationship with them. Although our parts electrically meet the
specifications of the Mac Pro systems, their custom cooling solution
incorporates additional thermal characteristics that require less
cooling than the standard FBDIMM heat spreaders. We are in discussions
with Apple to ensure our upcoming cooling solution for the Mac Pro line
of computers is inline with Apple's approved standards. Be assured we
will offer a complete product line once we have their approval.
(I asked about price impact for the revised modules-Mike)
After speaking with our product marketing team, the new design could
potentially impact cost. However, they are still finalizing those
details and don't have exact information to share at this point.
Thanks, Kelly
(Micron/Crucial)"
Update: on August 24th they started listing large heatsink FB-Dimms for Mac Pros (originally 512MB only, but now lists 1GB/2GB dimms also). A reader that had placed an order when Crucial originally listed (standard heatsink) Mac Pro ram sent a note wrote with a copy of the order reply:
"
I saw your article mentioning that Crucial no longer ships Mac Pro
memory. (Yesterday's news reader post that they no longer
listed Mac Pro compatible FB-Dimms. They had the day before
as mentioned/linked here.-Mike)
But I'd already ordered memory from them, this is the mail I received.
Thought you were interested to see this.
Regards, Dieter (from Belgium)
Mail from Crucial as of today:
"Hello, Thank you for your order placed with Crucial Technology. Unfortunately
there will be a delay in processing your order as we don't currently
have sufficient stock of the part you ordered. We expect delivery here
on 14 August and will ship the material to you as soon as possible.
My apologies for the delay.
Kind regards
ESTHER H.
Crucial Sales Administration
"
Dieter promised to report back after he received the memory There's many vendors offering FB-Dimms (with standard heatsinks) that should be functionally compatible, although with an unknown effect on Mac Pro fan speeds and cooling. (That Apple memory note/large heatsinks on the OEM dimms has created some concerns about using other untested FB-Dimms in a Mac Pro.) As of right now the only 3rd party FB-Dimms I know of with larger heatsinks are OWC's Mac
Pro memory. Still waiting for feedback from a Mac Pro user on FB-Dimm that don't have large heatsinks like the OEM Apple RAM. (Apple notes their large heatsinks were used to reduce airflow requirements/reduce fan speeds.)
If any Mac Pro owner uses FB-Dimms that do not have large heatsinks, let me know if you notice higher fan speeds than with the OEM memory or any other problems. Thanks.
(Update: On reader actually received his Mac Pro Crucial Memory. He added some supplimental (VGA) heatsinks on them but after several hours of use said ASP reported one of the dimms had a couple ECC corrections (2 errors corrected, not sure if that was heat related or just a suspect dimm). He's ordered other heatsinks to try. I suggested he return them and wait for the 'revised' dimms, but he said he was told they were not going to support the Mac Pro - perhaps the support person wasn't aware of what Crucial has told others (above).)
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