Whats Your OWC RAM Temps With New MacPro

[Play4keeps]

Can some ppl with the new mac pro post Temps of the Ram:
NETLIST VS OWC :Temps

[Spikeanator6982]

while they are not mine, and don't show netlist vs owc it does have owc on it. http://www.barefeats.com/harper3.html

[GangsterTalk]

while they are not mine, and don't show netlist vs owc it does have owc on it. http://www.barefeats.com/harper3.html

I found this quote interesting from this article:
"Some of you just want to buy two 2GB FB-DIMMs to add to the two factory 1GB FB-DIMMs for a total of 6GB. That configuration will slow you down. Don't do it. Again, the BEST performance setup is eight matched FB-DIMMs. The second best is four matched FB-DIMMs."

If the type of RAM is the same, why would having different capacities slow down the machine?

[junior77]

Go back and re-read the article...it's a lot to take in all at once, trust me I had to read it a few times to completely understand what was being said.

Basically, to get better speed performance you want to have a minimum of 4 sticks the same exact size, whether it be 4 x 1GB (4GB Total) or 4 x 2GB (8GB total). Not 2x1GB (OEM) plus 2x2GB (6GB total)...

[SolrFlare]

It's because you want an equal amount of ram per core. Quad channel for 4 cores, and octo-channel for 8 core. This will let the ram run faster. Bottom line, you want multiples or 2, 4, or 8 for your ram sticks for optimal performance. With 8 being the best for 8 core and 4 or 8 being equally good for quad core.

[Trishul]

Can some ppl with the new mac pro post Temps of the Ram:
NETLIST VS OWC :Temps

if you search you should find some people who have compared, and have found the Netlist runs hotter, that's why i went with OWC, who themselves said the same thing.

[drrich2]

That's an interesting article. Particularly for me, since:

1.) I've got a 2.8 GHz early '08 MacPro on order.

2.) Comes with 2 gig RAM.

3.) I want to upgrade to 4 - 6 gig RAM total.

4.) I've never had anything to do with online sales, so trying to unload the original 2 1-gig RAM DIMMS & just go with 2-gig modules from OWC isn't that appealing.

5.) I don't want a 20% drop in memory performance.

6.) I don't want to only use 1-gig DIMMs & limit the MacPro's memory capacity to 8 gigs. Would be great for now, but in 2 years maybe not so much.

So, what happens if I buy 2 1-gig DIMMs to make a 'matching quartet' of sorts, but later in addition buy 2 or 4 2-gig DIMMs? Do I still take a performance hit?

Richard.

[deathshrub]

It's because you want an equal amount of ram per core. Quad channel for 4 cores, and octo-channel for 8 core. This will let the ram run faster. Bottom line, you want multiples or 2, 4, or 8 for your ram sticks for optimal performance. With 8 being the best for 8 core and 4 or 8 being equally good for quad core.

This is entirely inaccurate. FB-DIMM RAM architecture has nothing to do with how many cores the machine has. Please don't spread untruths when you don't know what you're talking about.

[musicforme]

OWC 2 x 2 GB in riser B:

http://img.skitch.com/20080125-qtt7f9pnq33grn755t5q2yfbib.jpg

[Nosmot]

Hmmm my B2 Module is typically 12° hotter than it's partner, and both are hotter at all times than the OEM.

http://www.nosmot.com/imagine/owc_ram_temps.jpg

There's a picture here, you might have to hit reload to see it as my server is Canadian. ;)

I sort of assume this is a case of someone's first day on the job learning how to apply the thermal paste or something...

Oi! I forgot to mention it's two 2gb OWC chips in the lower RAM carrier.

[OWC Larry]

You have different airflow between the different riser and memory locations.

the 800MHz memory and AMB runs at a higher temp than 667MHz memory/AMB... just like a faster processor runs at a higher temp than a slower one. The AMB is rated to 225F, the memory to 190F.

1GB modules have more devices than 2GB, 4GB have higher density devices than 2GB modules.... Bottom line, more devices generate more heat - devices with more density, more circuit paths inside - also generate more heat. So - yes, a 2GB module will run warmer than a 1GB module.

In a normal server environment that uses JEDEC modules, you have high speed fans that push tons of air across keeping memory temps lower than what happens in the Mac Pro.

In the Mac Pro, you have the large heat spreaders to dissipate heat with higher surface area and a lower rate of air flow... that said, the temps are still higher than you'd have in a server, but WELL within spec.

About matching - each pair is a self contained unit. There is no performance hit for having 1 pair of 1GB from one MFR and another pair that is a different MFR. More performance occurs when two or more pairs are installed due to the multi-point access.. get 256MBit addressing with 2 pairs (one on each riser) vs. 128MBit with a single pair.

1GB vs. 2GB - 1GB modules are all Single Rank. 2GB modules are all Double Rank. The 4GB modules today are all Double Rank - although Apple may in the near future be adding support for Quad Rank (something we'll have to test in terms of performance benefit - but there should be a cost benefit vs. double rank). To be super simple, there is slightly better memory access performance with a Double Rank module vs. a Single Rank - which is why having at least 2 x 4GB Pair (2GB x 2) sets installed gives a benefit over 2 x 2GB Pairs installed or 2GB Pair + 4GB Pair installed. Having said that - the most SIGNIFICANT improvement comes with the adding of ANY 2nd Pair of memory where only a single pair is installed stock.

Hope this info helps. :)

Hmmm my B2 Module is typically 12° hotter than it's partner, and both are hotter at all times than the OEM.

http://www.nosmot.com/imagine/owc_ram_temps.jpg

There's a picture here, you might have to hit reload to see it as my server is Canadian. ;)

I sort of assume this is a case of someone's first day on the job learning how to apply the thermal paste or something...

Oi! I forgot to mention it's two 2gb OWC chips in the lower RAM carrier.

[kbmb]

You have different airflow between the different riser and memory locations.

the 800MHz memory and AMB runs at a higher temp than 667MHz memory/AMB... just like a faster processor runs at a higher temp than a slower one. The AMB is rated to 225F, the memory to 190F.

1GB modules have more devices than 2GB, 4GB have higher density devices than 2GB modules.... Bottom line, more devices generate more heat - devices with more density, more circuit paths inside - also generate more heat. So - yes, a 2GB module will run warmer than a 1GB module.

In a normal server environment that uses JEDEC modules, you have high speed fans that push tons of air across keeping memory temps lower than what happens in the Mac Pro.

In the Mac Pro, you have the large heat spreaders to dissipate heat with higher surface area and a lower rate of air flow... that said, the temps are still higher than you'd have in a server, but WELL within spec.

About matching - each pair is a self contained unit. There is no performance hit for having 1 pair of 1GB from one MFR and another pair that is a different MFR. More performance occurs when two or more pairs are installed due to the multi-point access.. get 256MBit addressing with 2 pairs (one on each riser) vs. 128MBit with a single pair.

1GB vs. 2GB - 1GB modules are all Single Rank. 2GB modules are all Double Rank. The 4GB modules today are all Double Rank - although Apple may in the near future be adding support for Quad Rank (something we'll have to test in terms of performance benefit - but there should be a cost benefit vs. double rank). To be super simple, there is slightly better memory access performance with a Double Rank module vs. a Single Rank - which is why having at least 2 x 4GB Pair (2GB x 2) sets installed gives a benefit over 2 x 2GB Pairs installed or 2GB Pair + 4GB Pair installed. Having said that - the most SIGNIFICANT improvement comes with the adding of ANY 2nd Pair of memory where only a single pair is installed stock.

Hope this info helps. :)

Larry, thanks for the info. Can you confirm what the optimum temps are for OWC qualified RAM? Tech support emailed me and said it's best to keep my 677MHz 2GB dimms under 73C.

I think most people are trying to put their minds at ease when it comes to RAM temps in the Mac Pro, without having to manually kick up the fans to cool them down.

By the way....what is AMB?

-Kevin

[Michael73]

I'll try not to get off topic too much but I have a new MP on order that's coming with 4 x 1GB of RAM.

I was thinking about ordering 2 x 2GB from OWC for a total of 8GB. Is BareFeets and others saying I should just hold off until I can afford 4 x 2GB?

[bigbird]

I decided to fill all slots of my coming MP. I ordered another 2 x 1GB so that now I'll have Riser A: 2GB 2GB 1GB 1GB
Riser B: 2GB 2GB 1GB 1GB

It seems to me that two sets of matched pairs filling all 8 slots is the way to go. I chose the extra 2 x 1GB because I didn't want to waste or sell the Apple stock 2 x 1GB.

With OWC Larry's post about MP 800 MHz RAM still being underpriced I decided to act today.

[OWC Larry]

You don't have to buy all 8GB at the same time... you'll get a boost adding 2 x 2GB now... you'll get the same benefit of adding 2 additional 2GB modules now or adding them 6 months from now...

But either way... your Mac Pro will be able to do things a good bit faster with 6GB installed (heck 4GB installed) vs. just 2GB.


---

AMB = Advanced Memory Buffer. It is essentially a processor that controls the memory access. Each FB-DIMM has its own AMB.

---

the 667MHz memory is fine up to about 170 F, although unless under heavy loads for extended times in a room with a high ambient temperature (non-air conditioned room near to the 95 F max environmental spec Apple supports for room temp where a Mac Pro is operating) temps typically are in the 110 to 150F range depending on the module size 1GB/2GB/4GD.

the 800MHz a tad warmer as prior noted... and typically should never have to manually turn the fans up or otherwise have auto fan speed increase because of memory temps so long as using modules with the Apple qualified heat spreader utilized. The processors and/or other components may need it... pretty typical too - even with stock min memory to have fans kick when higher end video card is under heavy load.

anyway - 73C = 127F and thats well below any danger zone. Proper spec memory works just as well at 127F as it does at max temp... the max temp being below the point where life span begins to be affected.

and of note - the main hot spot the high temps come from is that AMB.

We have shipped tens of thousands of Mac Pro modules and way back in August of 2006 even did the first heat profiling of modules that was publicly released. Did it mainly cause so many suppliers didn't have the right memory, were telling people that standard JEDEC shield modules were the correct ones (even Crucial initially shipped JEDEC shield vs. Apple qualified spreader modules), and we wanted to show people why that special heat sink was really needed and wasn't just fluff cause XYZ sellers said it wasn't needed.

JEDEC shield modules cool real well in the wind tunnels of the Xeon servers they are specced for. You can't even put Mac Pro spreader equipped into the Xserve and other like servers as the slots are too close as they don't have the room to begin with, but no need cause of the high speed fans blowing through them and out the back. Put those modules in the low flow Mac Pro memory chamber and, well, better let them cool before pulling them out or have gloves on... and the temps those non-Mac Pro modules reach is long term damaging to the devices on the modules as they exceed spec - mainly around the AMB which effectively will cook devices it is near to.

I'll try not to get off topic too much but I have a new MP on order that's coming with 4 x 1GB of RAM.

I was thinking about ordering 2 x 2GB from OWC for a total of 8GB. Is BareFeets and others saying I should just hold off until I can afford 4 x 2GB?

[GoKyu]

Larry: Nice to see you drop in :) Just got my 2nd order of 2x2gb RAM from ya, and running faster than ever - thanks :)

-Bryan

[kbmb]

the 667MHz memory is fine up to about 170 F, although unless under heavy loads for extended times in a room with a high ambient temperature (non-air conditioned room near to the 95 F max environmental spec Apple supports for room temp where a Mac Pro is operating) temps typically are in the 110 to 150F range depending on the module size 1GB/2GB/4GD.

the 800MHz a tad warmer as prior noted... and typically should never have to manually turn the fans up or otherwise have auto fan speed increase because of memory temps so long as using modules with the Apple qualified heat spreader utilized. The processors and/or other components may need it... pretty typical too - even with stock min memory to have fans kick when higher end video card is under heavy load.

anyway - 73C = 127F and thats well below any danger zone. Proper spec memory works just as well at 127F as it does at max temp... the max temp being below the point where life span begins to be affected.

and of note - the main hot spot the high temps come from is that AMB.



Larry, thanks for the reply. BTW.....your math is off a bit.

73C = 163.4F

That's mainly why I had the original concern with the 677MHz OWC 2GB modules that would consistently hover around 65C-70C (149F-158F) under minimal load, with ambient temps around 21C-24C (70F-76F)

I'm finding that increasing the CPU/Exhaust RPMs up to 600/700rpm helps bring the temps down.

-Kevin

[FastMan]

Larry,
Quick question. I recieved notice today that my 8GB's (4 2GB modules) of RAM I bought from you guys has shipped. Am I better off adding those two pairs to the stock pair that is coming with my Mac Pro (2 1GB modules) for a total of 10 GB's,,, or taking the stock 1GB modules out and just run the 4 2GB modules I'm getting from you guys?

Thanks.

[ProCreator]

Okay, if it is recommended to install memory in exponential growth of 2 (2, 4, 8, 16, 32), should I just install my 4 x 4G and leave the previously installed 2g out? Or would I see better performance with the full 18g's? :confused::confused::confused:

[FastMan]

ProCreator, we seem to have the same question. (Add to the stock, or yank it.)

[OWC Larry]

Leaving the stock 1GB x 2 pair in with additional memory will not reduce performance - more memory is ALWAYS better than less. Even in lower memory configs... we did extensive testing in the Core Duo / Core 2 Duo where you get interleaving with matched pairs. Better performance with 1.25GB than with 1.0gB 512MB x 2.. better to have 3.0GB (1GB + 2GB) than a matched pair of 1GB x 2 by a significant margin.

More memory trumps

http://eshop.macsales.com/shop/apple/memory/Macbook_Memory_Benchmarks

Okay, if it is recommended to install memory in exponential growth of 2 (2, 4, 8, 16, 32), should I just install my 4 x 4G and leave the previously installed 2g out? Or would I see better performance with the full 18g's? :confused::confused::confused:

[phjo]

I have a question for you, OWC Larry :

my 8-core 2.8 mac pro runs on 4*2Gb qualified OWC memory (800Mhz), as well as the two 1Gb stock ram.

Here are the temperatures of the first two banks of memory (under load, ambiant temperature : 68°F)

160°F and 169°F

(Those are OWC 2Gb sticks)

Are those temperatures acceptable on a long term basis, or should I bump a little the lowest fan settings for cpu/mem ?

phjo

[kirkbross]

OWC 2 x 2 GB in riser B:

http://img.skitch.com/20080125-qtt7f9pnq33grn755t5q2yfbib.jpg

What app are you using to get all your temps?

[WoOdPiPeS]

Mistake, sorry

[musicforme]

What app are you using to get all your temps?

iStat Menus (http://www.islayer.com/index.php?op=item&id=28)

[jb60606]

Word of advice: Invest in 2GB or 4GB modules.

I picked up 6x 1GB OWC modules to pair with my 2x 1GB APPLE Modules because I read somewhere that an 8-core Mac would benefit some from an array of 1GB modules (eight cores & eight 1GB modules???).

After installing the last 4GB today, memory temps -- at idle -- jumped about 10-15 degrees. Using HandBrake to rip a DVD brought the temp to the high 150s and low 160s thus far. I don't know what the danger-zone is for RAM, and my fan-speed hasn't increased thus far, but I don't like the big jump.

Attached are three snapshots:

4GB at Idle
4GB while encoding video using Toast
8GB ripping a DVD using HandBrake


Should I get rid of the 1GB modules and invest in 4x 2GB modules, or am I in no danger? I suspect these temps will increase during the summer.

PS: The Apple branded RAM are in bays A1 and A2.

And GOD DAMN did this beast of a machine rip "No Country for Old Men" fast. First time using HB; using default settings, it ripped the movie in less than 25mins. Now, I've never ripped a movie before, but I was expecting a longer wait.

[kbmb]

Word of advice: Invest in 2GB or 4GB modules.

I picked up 6x 1GB OWC modules to pair with my 2x 1GB APPLE Modules because I read somewhere that an 8-core Mac would benefit some from an array of 1GB modules (eight cores & eight 1GB modules???).

After installing the last 4GB today, memory temps -- at idle -- jumped about 10-15 degrees. Using HandBrake to rip a DVD brought the temp to the high 150s and low 160s thus far. I don't know what the danger-zone is for RAM, and my fan-speed hasn't increased thus far, but I don't like the big jump.

Attached are three snapshots:

4GB at Idle
4GB while encoding video using Toast
8GB ripping a DVD using HandBrake


Should I get rid of the 1GB modules and invest in 4x 2GB modules, or am I in no danger? I suspect these temps will increase during the summer.

PS: The Apple branded RAM are in bays A1 and A2.

Get smcFanControl and set the min fan speeds to even a little higher and you'll notice your temps go down.

Typically, 2/4GB modules will run hotter than the 1GB modules. However, in your case your adding more heat because you are physically adding more modules. Not sure you'd see a huge difference temp wise moving to 2/4GB modules.

I bumped my CPU fan up just 100rpm (which bumps the exhaust up as well) and I'm seeing nice reduced temps. That's with just 100rpm more! It's till only running at 600rpm. I can take it up to 1000+ without any real noise.

-Kevin

[jb60606]

Get smcFanControl and set the min fan speeds to even a little higher and you'll notice your temps go down.

Typically, 2/4GB modules will run hotter than the 1GB modules. However, in your case your adding more heat because you are physically adding more modules. Not sure you'd see a huge difference temp wise moving to 2/4GB modules.

I bumped my CPU fan up just 100rpm (which bumps the exhaust up as well) and I'm seeing nice reduced temps. That's with just 100rpm more! It's till only running at 600rpm. I can take it up to 1000+ without any real noise.

-Kevin

cool - thanks. I just downloaded smcFanControl version 2.1.2, increased CPU/Exhaust setting by 100RPM and the RAM temps appear to be dropping into the 120s.

[kbmb]

cool - thanks. I just downloaded smcFanControl version 2.1.2, increased CPU/Exhaust setting by 100RPM and the RAM temps appear to be dropping into the 120s.

Glad to help.

You can setup multiple profiles in smcFanControl to adjust for different settings, like the temps in the summer, etc.

Also, once smcFanControl has set the fan speeds.....you can close the app. Those settings will survive a reboot. They won't survive shutting the machine down. But you don't have to have the app running all the time.

-Kevin

[jb60606]

Glad to help.

You can setup multiple profiles in smcFanControl to adjust for different settings, like the temps in the summer, etc.

Also, once smcFanControl has set the fan speeds.....you can close the app. Those settings will survive a reboot. They won't survive shutting the machine down. But you don't have to have the app running all the time.

-Kevin

I'll be adding 3 more hard drives (to create a RAID array) tomorrow, so you couldn't have recommended this app at a better time. Thanks again.

[bigbird]

I've got all 8 RAM slots occupied, 4 hard drives, 2 optical drives and with SMC fan control I can hold my RAM at 51C (124F) by having all fans at 1000 rpm. It's still fairly quiet. I haven't used handbrake yet, but for video encoding it is FAST!

[GotPro]

Just for comparison... here are my temps with the stock Apple ram in Dimm Slots A1,A2 and Transintl.com Memory in Dimm Slots B1,B2

Note: This is UNDER LOAD during a HandBrake Queue Session that's been going on for 2+ Hours.

[jb60606]

Just for comparison... here are my temps with the stock Apple ram in Dimm Slots A1,A2 and Transintl.com Memory in Dimm Slots B1,B2

Note: This is UNDER LOAD during a HandBrake Queue Session that's been going on for 2+ Hours.

Damn. Is your apartment's ambient temp in the 60s or something? Those CPU/Ram temps are ice cold in comparison to mine.

[GotPro]

Damn. Is your apartment's ambient temp in the 60s or something? Those CPU/Ram temps are ice cold in comparison to mine.

Not so much... I'm in Dallas... so I'm sure it's colder up there... unless you have your heater on full blast :-)

However... I do have SMC Fan Control installed and set the minimum fan speeds across the board to 900RPM.

This seems to keep things running nice and cool, and is still WELL within a pleasant fan noise range.... there is just a very quiet whisper to the fans.

Of course I could be biased... my last "box"... non-laptop machine was a piece of CRAP DELL P4 2.4Ghz... that sounded like a freakin' Jet Engine.

So... I may be biased :D

Oh, fwiw... the air conditioning is set to about 74 in my apartment.