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New PowerMac G5s: Up to 2.5Ghz, Liquid Cooled
no_demons writes "Apple have just announced the new, completely dual-processor PowerMac G5 lineup. The models all sport an 8x SuperDrive, whilst new the dual-2.5GHz model also features an 'innovative liquid cooled heat sink,' available in July."
I think the 2.5 model, with the whiz-bang cooling and new chips, is the first next-gen G5, whereas the lower models are designed to clear out old supplies. November will see the real "bump" to 2.5/2.7/3.0 all-liquid series.
Here's a theory: The 2.5 is slated to start shipping in July, so maybe Apple is getting around the new-model-launch-delays bear? Will they announce and ship the "missing" 2.7 and 3.0 portions of the range in September, when they would have shipped anyway, even if they were announced today? "Clearing out the old machines and releasing the typical low-end 'shipping today' portion of the new model range, and keeping mum on the parts we would normally delay two months."
That said, they are still impressive machines, save for the GPU. Also, to the first poster, the top end chips are 2.5Ghz, not 1.5...
I like the idea of liquid cooling but I also like simple systems. There's too much complexity here. So...
I've often pondered creating a sealed aluminum case with integrated heatsink. Stick the components in and fill it with dielectric oil in order to create a huge, passive heat sink (like a big transformer or whatever). Thoughts? I almost got around to this but stopped after submerging an old hard drive in some dielectric - if you seal the breating hole, it works fine (I believe the hole is there to relieve pressure differentials caused by changes in altitude so it should be fine in a stationary location).
Provided that the dielectric has good enough heat transfer, this should work, no?
Life is the leading cause of death in America.
There may come new Displays (20, 23 and 30 inch with the known aluminum brushed metal look) to the WWDC, as reportet here.
Think Secret writes they may even come with DVI port.
>> Had I been going to bed earlier every night? Have I been sleeping later? Has Tyler been in charge longer and l
I like it when Jobs does his old "oh, and one more thing..." also. I think the WWDC will have something bigger than new G5s though. I'm guessing it will be bigger than a new iMac. With the release of AirPort Express and such, the low-fanfare announcement of the new G5s, but more importantly the setup of an entirely new division dedicated to the iPod, I'm guessing we'll see a new consumer product. You gotta love the rumors that fly around the Apple camp. I'm taking stabs at what the next unveiling will be also...but it sure is fun. New consumer product...hmmmm...
"He uses statistics as a drunken man uses lampposts...for support rather than illumination." - Andrew Lang
I disagree. This is what I did to mine: http://www.buckeyemonkey.com/images/dualblue2.jpg
Well, IBM was the first to go on record as saying that 90nm was considerably more difficult to implement than they first expected. There's a lot of current leak going on, meaning wasted power, which leads to increased heat (see Intel's Prescott as a very good example). Supposedly AMD's having some 90nm issues as well now.
I guess those issues would explain why Apple had to switch to liquid cooling for this round of systems.
in contrast the mac case has layers of flowing air no thicker that what is probably the thermal diffusion length. Air flows over the top and bottom of the hotest items and does so in one pass. Its beautiful. and mac planned this out from the beginning for expandability.
besides I like the cheese grater.
Some drink at the fountain of knowledge. Others just gargle.
I'm no hardware engineer, but looking at this artist rendering (akamai.net is an image host for all Apple.com images) of Apple's liquid cooling system, I think the processors are getting different cooling.
It would appear that the liquid passes over processor #1, then #2, then back to the heat sink to be diffused by the fan blowing over it. This would say to me that processor #2 is getting at best room temp water cooling, while proc #1 is getting cold water cooling.
Here's my reasoning: If the heat sink with the fan blowing over it can cool the water 2X degrees, then when it is leaving the cooling system it is at Room Temp (RT) - X degrees. It passes over both processors and returns to the cooling system at RT+X degrees, where it is cooled by 2X and leaves the system at RT-X, headed for the hot processors again, follow?
So here's the meat of it: both processors together heat the water up by 2X (see above). That means each processor heats the water by X, so when the cool water leaves, it is at temp RT-X, passes over the heat sink and it raised to (RT-X)+X=RT which then passes over the second processor and cools it to RT+X where it returns.
So the second processor is getting room temp water cooling while the first is getting RT-X cooling. What effect will this have on the system?
I only came here to do two things; kick some ass, and drink some beer...looks like we're almost out of beer.
For my applications un-optimised code on a 2 Ghz G5 runs about the same as on a 3 Ghz Pentium and a 2.4 Ghz Xenon, if I optimise the G5 code with xlf and shark I get my 2 Ghz G5 to run twices as fast as the Pentium or Xenon... but I don't have the intel compiler for the P4 or Xenon so that's not a fari comparison.
Anyway I expect this new G5 to greatly outperform a P4.
There are 10 types of people in this world, those who can count in binary and those who can't.
Well, here at work, we have a handful of Dell desktop machines and we were also the first on our block to get the dual 2Ghz G5. I can tell you for certain that the Mac is WAY quieter than these particular Dells (YMMV of course).
It's not so much that the Mac is amazingly quiet for having 9 fans, it's amazingly quiet for having any fans. They could definitely get away with 2 fans, but they'd have to run faster so they'd be louder.
The liquid cooling thing is all part of it...you know the kind of fans you're typically running on a new Intel/AMD chip? Well if you liquid cooled them like this Mac, you could probably get away with a much quieter setup. Again, I'm sure they could air-cool them, but they'd be loud like your typical PC.
teeker
Think Secret is reporting that new displays are due soon. The new displays apparently will be DVI only -- no more ADC. (The 30" display requires 150W, which ADC couldn't handle.)
What puzzles me is the GPUs currently in these new G5s -- they seem to be dual-head ADC+DVI. That's not terribly useful once ADC goes the way of the dodo. If you're in the market for the new displays, it might be worth holding off on the G5 a few weeks, in order to get a DVI+DVI video card.
If you want the machine, buy it and upgrade incrementally. There's no law that says that the second you buy your machine you have to load it up with memory and disk.
My dual 2ghz G5 performs great with the stock 512mb RAM. I've upgraded it to 3.5gb, and there is a difference (mainly in switching applications), but the system with its stock RAM configuration is perfectly usable.
My 160gb system disk lasted about 8 months before I had to buy a new 250gb to fit the empty slot. I would have gained nothing by buying the 250g disk with the system.
Apple makes fantastic computers, and I'm a fanatical Apple loyalist -- but you'll get everything cheaper if you go to Fry's(*) or shop on the net for components like memory and disk. Memory upgrades are universally about triple the going rate if you get them from Apple, and Apple's brilliant case design makes them easy to install.
Always upgrade incrementally. It will let you spread the financial pain and you'll enjoy getting the performance boost treats spread over time.
Hope that helps.
D
(*) If you're not in California, you may have never heard of Fry's. It's a huge retail store, designed by scions of a prominent supermarket family, that works basically like a supermarket for computer gear. If it exists, and it has to do with computers or salty snacks, it's probably hiding somewhere in Fry's, waiting patiently for you to discover it.
The myth that Apple is more expensive is just not true, as anyone who has done a serious comparison of features will tell you.
Sorry, but it used to be true. The G5's are the first systems Apple offered that are a reasonable deal compared to PC's. Honestly, I'd like to see a $1000 machine based on a 1.6ghz G5. Then Apple would really turn some heads.
And Apple monitors, while excellent, are still too pricey. They need a $400 17" DVI-D only model or something.
Look at the iMacs... a 1ghz G4 with a 15" LCD for $1300? I could get a MUCH faster Athlon64 system for that with more RAM and disk space, plus it would be upgradable.
Yeah, you're paying for the software and the "experience", but frankly, most people don't care enough to plunk down the extra cash, and they still have to pay another $200 (or more) for MS Office when cheaper PC's come with it for free.
Lex orandi, lex credendi.