More Liquid Cooling Diagrams

[aafuss1]

According to 'The Inquirer' some of the AppleInsider images of the cooling system had to be removed :
http://theinquirer.net/?article=16646

But these images can still be viewed:
http://images.appleinsider.com/images/g5lcs2.gif
http://images.appleinsider.com/images/g5lcs1.gif

 

[Maxx Power]

This is Lame

The apple marketing guy is a bozo. He obviously is good at marketing though, which is probably why apple hired him. Challenged power density ? That's just a fancy way of saying -> "I work in marketing, and i have no idea what i'm talking about except what the guys above me tells me to say and think, and i dress in bright bright pink".

Power Density Increased, because per interconnect size decreased. The total number of transistors remain roughly the same (no change of processor implementation). That means the area of the die got smaller, which means per unit area heat dissipation increased if clock speed is increased from previous generation. Density may have been increased, but the total is what matters, you see your desk lamp ? It's so hot and bright because the effective heat dissipation per unit area is high, so you probably wouldn't want to touch a 60 watt bulb in operation. In contrast, your bathtub water heated to a comfortable temperature lets out more than 60 watts of heat but hardly hot to the touch.

Bottom line is, the only reason they used water cooling is obviously because the new G5's are dishing out too much entropy compared to previous generations. I don't know what kind of a clown would believe the PR marketing firm of ANY company.

 

[LethalWolfe]

Problem is anyone who's actually used all of those programs know that there is no direct way to compare them. For instance, for CubaseSX2 vs LogicPro, what constitutes the reverbs or the track count, what audio equipment is being used in conjunction, etc. For video, what makes up "supporting" the number of video layers.. real-time rendering, just playback, etc. Plus, why would you compare to Avid MC and not AvidXpressPro (which supports 12 realtime layers out of the box) or Avid Adrenaline (which supports alot more.) Either way, real professionals are not swayed by marketing numbers. They'd have a specialist sales rep show them the machines and actually use them in comparison. These silly numbers are for general laymen to say "machine x" is more powerful than "machine y", but it doesn't mean anything to actual users who make real money off of the product.

AvidXpressPro can do 1 stream of uncompressed SD video in real time. Please provide a link that says it can pull 12 streams of DV in RT. FCP 4.5 + a dual 2.5 G5 can pull more SD streams in RT than an Avid Adrenaline running dual 2.8 Xeons. Not to mention it costs a hell of a lot less.

Is this an end-all, be-all stat? Or even a very important one? No, but it's a good eye catcher and that's why it's there.

And of course you are going to pit Apple hardware + software against "PC" hardware and software. This is marketing the Apple platform against the PC platform.

"Real pros" don't base decissions off of sales reps demos. They talk to other pros, request demo units to play with on their own, and look for info in the trades. Going by the word of a sales rep is worse than going by what you see on the company's website.


Lethal

 

[Sun Baked]

Well it looks like he is guessing at this number...

... (maximum wattage of 102 - I'm assuming this figure from the typical)
... Let's say that the 970fx at 2.5ghz is the same as the 130nm part at 2.0ghz

It would be great to see some real documentation in regards to the 970 and 970FX parts. To bad IBM doesn't appear to put in any out at the moment.

Not quite double, but it's close enough for estimates until somebody can extract the real numbers from IBM.

Searching around, there was a thread here about this article putting the 970FX at 50W for a 2.5GHz unit...

http://www.infoworld.com/article/04/02/16/hnpowerdown_1.html

 

[Phinius]

You calculations might be off a tad bit.

The 2.5GHz PPC970FX operates at a maximum power dissipation between 100-110W -- the 2.0GHz PPC970FX (50-55W) and below chips operate at much lower maximum power dissipation numbers.

The Pentium 4 Prescott at 3.4GHz uses a maximum of 127 watts. With the 970FX potentially achieving another 20% boost in frequency to 3GHz, it could have a higher maximum power use than a 3.4GHz Prescott P4 if your calculations are right.

 

[dongmin]

Something from the barefeats article that caught my eye was the comment that the new dual 2.0 is identified as 7,3. I would assume the dual 2.5 is also. Which makes one wonder what 8,1 is....???

There's been at least 3 threads on this topic. The consensus is that the 8,1 is a brand-spanking new iMac with totally new architecture (meaning G5 or e600). Please see

https://forums.macrumors.com/showthread.php?s=&threadid=73831

 

[legion]

AvidXpressPro can do 1 stream of uncompressed SD video in real time. Please provide a link that says it can pull 12 streams of DV in RT. FCP 4.5 + a dual 2.5 G5 can pull more SD streams in RT than an Avid Adrenaline running dual 2.8 Xeons. Not to mention it costs a hell of a lot less.

Is this an end-all, be-all stat? Or even a very important one? No, but it's a good eye catcher and that's why it's there.

And of course you are going to pit Apple hardware + software against "PC" hardware and software. This is marketing the Apple platform against the PC platform.

"Real pros" don't base decissions off of sales reps demos. They talk to other pros, request demo units to play with on their own, and look for info in the trades. Going by the word of a sales rep is worse than going by what you see on the company's website.


Lethal

A) I never said 12 streams in uncompressed.. but it can do 12 streams 5:1 (DV25).

B) I also said that real pros don't go by marketing, but use the software and hardware. No one takes the word of anyone when you can get demo machines to work with (if you have the budget) I never said that anyone would go "of sales reps." I said that real pros demo the software provided by a sales rep.

Also, lets not get confused as to what FCP is capable of at film quality. I think you and I know who uses FCP and who uses Avid when it comes to big budgets and finishing and onlining video.

The basic question, though, is why Apple didn't do comparisons using the same software as the ones they chose run on both platforms (Cubase SX2 and Avid) Would it be that they know they wouldn't have anything to tout???

 

[Peej]

tje reason the density is such a problem is because you can longer cool the heat with a fan, its so hot in such a small area the air would never cool the center of the chip, just the edges. a liquid cooled device is able to pull heat off the entire chip.

but that would require far more common sense than they have...the simplicity of this idea boggles the mind

It's not a cooling area problem (middle vs sides), it's that the chip can be cooled more efficiently with a liquid than with air. Liquid (water plus additives to preserve it and raise the boiling point) is more dense than air, and can therefore be a much more efficient conductor of heat, in this case it takes it away from the source. Being a liquid, it can flow over the heat source and then into an area where it can be cooled by a fan, then recirculated to the heat-producing area again. Try this experiment: Put a can of warm soda in the freezer, make sure it's not touching anything, and put another can in a bucket of ice water. Wait 15 minutes. See which one is colder. Hey, that's it. G5 powerbooks will come with water-proof cases and aluminum ice buckets. Yes!

peej

 

[savar]

Well, the point is that the old 970 were not able to reach 2.5Ghz - the higher density allows for the speed increase - which brings a higher power dissipation. Furthermore the smaller structural size leads to the same amount of transistors on a smaller surface area, thereby exacerbating the problem.

I thought that when the chips shrank, the power consumption shrank also. So that 2.0 ghz on a 110 process consumers more power than 2.0 ghz at 90. Is this not true? Or does the increased density more than offset this savings?

 

[jbrown]

Do you have to.....

.....top up with anti-freeze in November

Are these the same chips in the xServes?? If so why no liquid cooling in them?

Also, what is the liquid? I thought I read water - which is an active compound I believe.

What if it leaks? Say 5 years down the line.

 

[displaced]

I thought that when the chips shrank, the power consumption shrank also. So that 2.0 ghz on a 110 process consumers more power than 2.0 ghz at 90. Is this not true? Or does the increased density more than offset this savings?

Thinking back to my days when I had time to care about overclocking and all that stuff...

A die shrink means smaller chip features & interconnects. That means you need less voltage to make the chip work. This is good, because as you raise the clock speed you begin to get electrical interference within the core. Lowering the voltage means less interference, and thus higher clock speeds.

Lowering the voltage also means it's less power hungry and, nominally, a cooler CPU. But, by the time you've cranked the clockspeed up (which you now can because of the voltage reduction) you're still spitting out a lot of heat. Plus, the smaller die size (surface area) means it's harder to get rid of that heat.

 

[AidenShaw]

Apple's instructions for handling leaks

What if it leaks? Say 5 years down the line.

Apparently, Apple's anticipated this already:

http://www.apple-x.net/modules.php?...&POSTNUKESID=03dfab6176dccb4d5f83a36b15819375

Of other interest, "Nitrile or rubber glove should be worn when handling an LCS module that is leaking or suspected to be leaking.

Evidence of leaks would include corrosion around fittings in the LCS coolant system, a light green or red liquid present, or a slick or slimy feel when handling the part.

For leaks or spills, wipe up the fluid using rags, paper towels, or other suitable materials. Dispose of all cleaning materials according to local laws and regulations ...

Note that the Apple LCS uses simple spring type hose clamps on the hose connections. In contrast, one of the overclocker's water-cooling kits from http://HighSpeedPC.com uses positive compression fittings instead:

http://www.highspeedpc.com/Merchant...e=HSPC&Product_Code=CMSkit&Category_Code=Kits

 

[eazyway]

power density

"power density"



...obviously a marketing guy

Actually makes a lot of sense since we went from a 135 nm chip to a 90 nm chip if the total power output is the same for each chip then the density on the 90 nm is much greater. Power per unit of area. More heat radiating per sq nm. Thus the higher temperature and the cooling problem.

 

[MacUnit]

Cooling, Fans, Noise

Actually makes a lot of sense since we went from a 135 nm chip to a 90 nm chip if the total power output is the same for each chip then the density on the 90 nm is much greater. Power per unit of area. More heat radiating per sq nm. Thus the higher temperature and the cooling problem.

OK, that makes sense. But that would imply that the new 1.8 and 2.0 machines are going to be LOUDER than the old 1.8 and 2.0 machines because they do not have the enhanced (liquid) cooling but still need to dissapate more heat (per unit area).

Do we all expect the new machines without the LCS to be noisier than the old ones? Will the fans have to be on more at higher speeds?

---MacUnit

 

[shawnce]

OK, that makes sense. But that would imply that the new 1.8 and 2.0 machines are going to be LOUDER than the old 1.8 and 2.0 machines because they do not have the enhanced (liquid) cooling but still need to dissapate more heat (per unit area).

Do we all expect the new machines without the LCS to be noisier than the old ones? Will the fans have to be on more at higher speeds?

I don't expect them to be any louder and in fact I expect them to be quieter on average.

Remember they actually dissipate less heat then the prior versions (sure in a smaller area die wise however note the chip package is the same size as the 970, 25mm x 25mm) so overall you have less heat to remove from the system. One can assume that the current passive air cooling used is sufficient to pull heat fast enough from the 1.8 & 2.0 GHz chips and hence they do not need the liquid cooling. If they can pull out the heat fast enough you will likely not need any additional air flow and in fact you may likely need less air flow because the chip dissipates less overall. Again the chip package for the 970 and 970FX is the same size/type and they [IBM] have likely done their best to get the heat to spread rapidly out of the whole of the package as much as possible.

In fact the 2.5 GHz doesn't _need_ the liquid cooling either given that top end P4 have higher power densities then the 970FX at 2.5 GHz and those systems ship without liquid cooling.

I still contend that it is only being used now because Apple expected to have faster chips around this time that would really need to be liquid cooled to be efficient/safe/quiet and they want to start using the system to help bullet proof it for when it very much needed and they had it ready and stocked obviously.

With that said, their is no doubt that using the liquid cooling for the 2.5 GHz will help keep it quiet since it can pull heat out of the chip more efficiently and spread that heat out, evenly and efficiently, to a large cooling surface then a passive cooling system would.

 

[MegaSignal]

Quieter - I doubt it!

I'm not sure about the Rev.
But generally the water cooled are alot quieter because of less fans

Because there will still be the other fans for the other sections of the cabinet, as well as fans for the radiators, plus all of the ancilliary motors/pumps/whatever for the LCS, it will probably be a "wash" in terms of overall noise.

I'll bet money on it.

 

[SiliconAddict]

We're what? A week and a half away from WWDC and this is the best rumor that can surface at this point!?!?!??! (Note that this isn't a hack on you Arn.)

WEEEEEE!!!! LC diagrams are released! OMG!! OMG!!! This is so much better then your typical rumor!

Where's the video iPod? Where's the rumor about Apple's Tablet? G5-M PowerBooks?

I want rumors dang it!!

 

[Jeff Harrell]

Plus, why would you compare to Avid MC and not AvidXpressPro (which supports 12 realtime layers out of the box) or Avid Adrenaline (which supports alot more.)

They did use Adrenaline. I just oversimplified.

These silly numbers are for general laymen to say "machine x" is more powerful than "machine y", but it doesn't mean anything to actual users who make real money off of the product.

What was the point of this post? Just to be derisive?

I have absolutely had it up to here with people who do nothing but whine about benchmarks and performance tests. If you don't like the results, that's fine. But kindly shut up about it. And leave your "I'm better than you because I snort at glossies" attitude at home. I use a Mac specifically to stay away from that kind of elitism.

Try this experiment: Put a can of warm soda in the freezer, make sure it's not touching anything, and put another can in a bucket of ice water. Wait 15 minutes. See which one is colder.

Here's a much more dramatic experiment: free two blocks of ice in the same size. Put one in a 400-degree oven. Put the other in a sink full of slowly running cold water. See which one melts first. The degree to which water is a better conductor of heat than air has to be seen to be believed.

 

[jsw]

What was the point of this post? Just to be derisive?

I have absolutely had it up to here with people who do nothing but whine about benchmarks and performance tests. If you don't like the results, that's fine. But kindly shut up about it. And leave your "I'm better than you because I snort at glossies" attitude at home. I use a Mac specifically to stay away from that kind of elitism.

To some extent, I agree with legion in that benchmarks do not reflect reality for most users unless they happen to do exactly what the benchmark tests.

That aside, though, they are a useful tool for more than just "general laymen" in that they give an idea of relative performance/software strength. Yes, if your business depends on application X, then of course you'll want to see that on each platform to decide what makes sense for you. However, even if, from a purely hardware point of view, two systems are equal, it so happens that the benchmarks show one as being consistently slower, then it indicates to me that software development for the "slower" platform isn't as strong, which is useful for me to know.

So, therefore, I think benchmarks are very useful in that (limited) sense.

However, since I'm not a graphics pro, I really don't care how much faster/slower the G5 is compared to an AMD PC. To me, OS X is such a better OS that, unless the hardware starts to fall SERIOUSLY behind, I don't care what the numbers are.

 

[wdlove]

Should there be any concern about the connectors that Apple is using, as mentioned above?

How will heat and humidity affect the cooling system? Wondering if there might be a condensation problem during high humidity. We have Dew Points in the 60's a lot here is Boston. Occasionally the 72 range.

 

[DWKlink]

Wow, looking at the picture of that PC pump posted a few replies back makes you really appreciate the engineering of apple products. The apple LCS just looks like its much more rugged and built of much higher quality materials and craftmanship.

 

[dizastor]

I've had a liquid cooling system in my pants for years

 

[g4cubed]

we'll see

Because there will still be the other fans for the other sections of the cabinet, as well as fans for the radiators, plus all of the ancilliary motors/pumps/whatever for the LCS, it will probably be a "wash" in terms of overall noise.

I'll bet money on it.

I didn't say all the fan. But I guess, to some extent you're right. I've seen a couple of water coolers that were whisper quiet and others noisey as hell. I guess we'll have to see which one Apple selects.

 

[shawnce]

Should there be any concern about the connectors that Apple is using, as mentioned above?

How will heat and humidity affect the cooling system? Wondering if there might be a condensation problem during high humidity. We have Dew Points in the 60's a lot here is Boston. Occasionally the 72 range.

The liquid cooling system used isn't an AC unit (no compressor or evaporator and the cooling fluid doesn't change density/vaporize) so it doesn't have the ability to cool a target location more then the ambient temperature of the fluid. The liquid cooling system is simply about pulling heat away from one location rapidly and efficiently and transferring that to a much much larger surface area, one that is configured to be air cooled efficiently. It isn't about cooling that surface below ambient temperatures like your fridge or AC unit does.

So I doubt you can get into a situation that can result in condensation build up (without changing the environment the system is in rapidly).

 

[AidenShaw]

Wow, looking at the picture of that PC pump posted a few replies back makes you really appreciate the engineering of apple products. The apple LCS just looks like its much more rugged and built of much higher quality materials and craftmanship.

The Apple piece looks more elegant, but of course it should - it's a custom designed piece for one particular computer. The PC part is a universal kit, designed for the hobbyist to adapt to his particular case.

As far as quality - I don't know how one can judge the quality of the pumps, seals, soldering and other details from the photos.

It's very bizarre, however, that Apple is using rubber hoses and spring clamps instead of metal tubes and fittings, or compression fittings. It looks like there are 16 clamps in the system, that's a lot of potential leakage points.

At the very least Apple could have used screw-type clamps instead of those spring loaded clamps. But, I guess the extra expense of higher quality clamps would have eroded the profit margins.

Also - where's the expansion tank?. It doesn't look like the Apple unit has any provision for dealing with the expansion of the fluid as it warms up. Does it just let the pressure increase to push against the seals and spring clamps? Maybe all the rubber hoses swell to absorb the pressure.


BTW, here's what the PC kit normally looks like when installed in a system: