How loud is the Mac Pro under heavy load?

I can't compare it against a Quad G5 but coming from DP 1GHz G4, my MP is virtually silent. In all seriousness, It's darned near sleep mode quiet! I hear the whir of my (fan-less) FW drives more than anything else and they're the same distance (3ft) from me as my Mac Pro. I haven't put it into full production yet but I have pushed it here and there and haven't ever noticed the fans ramp up. I think it's a safe bet that the MP is much quieter than a Quad - especially under load.

Mac Pro 2.66 Mac OS X (10.4.7)

The CPUs are passivly cooled by heatstinks - there is no fan on the CPU.

The fans never change in speed or volume - no matter what you are doing.

The only thing you'll hear when you're rendering is the HDDs ticking away.

I don't mind it however I don't see why HDDs still have to make noise - they should be dead silent by now.

I mean no harm but I must disagree. The fans do change depending on amount of installed ram and the amount of stress they are under along with the rest of the system load. I don't think you can ever say a computers fans will never vary depending on use, it's just not accurate. And HD's will almost always make noise, it's caled friction. My MP has had a slight fan sound increase because of my Ram upgrade but nothing that is too noticeable.

Did you install 3rd party RAM?

I have stock Apple RAM and no what I'm doing... if I have 20 apps once at once encoding or nothing open - the fans NEVER EVER change in speed or volume.

If you're fans are changing in speeed or volume I would suggest you have a faulty unit and to get it checked out.

I have ram from Crucial which some are reporting are the exact same modules that shipped with their MP's. I don't think you can state that an increase in fan noise or function is automatically a sign of faulty manufacturing, or a problem with the machine. For every single computer I have owned, PC's and Mac's, the fans have spun at a higher rate when under heavy load. I may be wrong but I wouldn't think that Apple has created a computer that has fans that only spin at a certain defined speed and never change. But like I said I could be wrong.

Maybe your room's temperature is low enough that it is easier to dispell or heat doesn't build up enough. I just realized I've never heard any cycling of fans or kicking in during startup that I can recall unless on booting from the Install disk. And now that weather is cool-chilly today, unlikely.

Still getting use to MP and haven't had a chance to work in iDVD or something... which should be fun.

I have 1 GB of additional ram installed (from Crucial) and I can hear the fan running but it is not significant at all. The computer is about 3 feet from me on the floor. The most noticable and a little annoying is the Hard Drive noise. I never heard the hard drive on my iMac G5 but it is very noticable on the new MacPro. Both the factory installed drive and the new drive that installed (Western Digital WD500KS).

Is the hard drive noice noticable to anyone else? Granted, I am in a very quiet environment. I work from home so when my toddler isn't running around under me it is pretty quiet in my office.

SilentPC reviews drives and gave the WD Caviar SE16 500GB the best (lowest) measured dB of any drive. Which is hard to believe when you have 5 platters spinning.

I have two 320GB RE versions that are really really quiet. If you move everything over to the 500GB and remove the the OEM drive - or move it so it is in the back - I even think it helps to not have two drives next to each other.

Coming from different computers, my B&W drove me crazy but not the Beige G3, and when someone said the MacPro was near silent" that was enough for me. And I don't regret it. My MDD 1.25 (single cpu) meant the TV in my office had to be turned up - very annoying 3 yrs.

What I'm trying to figure out is if the Mac Pro is as loud as the Quad when you are doing some really, really big renders that use 4+ threads (400% CPU Usage).

Well at 400% cpu usage my Mac Pro sounds the same as it does when idle - very quiet.

The fans are definitely variable speed. I've only heard mine spin up once, and that was during an Eclipse development session in which I had inadvertantly introduced an infinite recursive loop (the CPUs were VERY busy doing nothing, very fast... 🙂. Sound of the fans faded to nothing a few seconds after killing the process. My old WD 200GB drive is the loudest thing in my quad pro; The stock drive is nearly inaudible. BTW, I've got 2GB of stock apple RAM - no third party memory.

I definitely noticed it when the fans spun up - compared to the normal sound output of my box, it was REALLY loud. Ironically, I think it was still quieter than my Athlon 1800+ machine that the pro replaced.

BTW, nearly silent drives are available, they're just a lot more expensive. Check out the build-your-own-Tivo sites for tons of threads on this subject.

2 gig total (added 512x2), compared to 1.8 gig single cpu g5 this machines is QUIET!!. By comparison, seems totally silent, loudest by far sound is from hard disks.

I have a dual 2.0 GHz Rev. A G5 and now am using a MP 3.0 GHz. The G5 is louder at idle than the MP is at full throttle. I decided to see how loud it would get but maxing out all 4 cores overnight. I came into the room the next day and was bummed it had crashed because it sounded like it had shut off but I moved the mouse and to my delight the thing was still churning away at 400%. It is very very quiet and I have slowly gotten used to the fact that it is nearly impossible to tell if it is asleep or awake. The G5's seem to have a very large delta with regard to fan noise, not so bad at idle and kinda loud when fully loaded. The MP's seem to go from nearly silent to barely audible.

Someone mentioned above that the machine has only passive heat-sinks on the CPUs which is true but misleading because each heat-sink has a dedicated fan right in-front of it in the case. So far I have added 4x1GB of non-Apple thermal spec RAM, i.e. no heat-sinks - just spreaders, and the fans have not spun any louder. Two of the sticks are Kingston and two are Crucials which were the wrong types due to an error by them and didn't have the Apple-style sinks on em. The Kingstons have run reliably for over a week with me stressing them almost every night and I have encountered a lone ECC error which was corrected. I think in cooler environments you may be OK with regular FB-DIMMS but in a hotter environment you may have issues, I keep it pretty cool where the MP lives.

-Jerry C.

Did you install 3rd party RAM?

I have stock Apple RAM and no what I'm doing... if I
have 20 apps once at once encoding or nothing open -
the fans NEVER EVER change in speed or volume.

If you're fans are changing in speeed or volume I
would suggest you have a faulty unit and to get it
checked out.

You mean you 'KNOW' what you are doing.

My MacPro also can get louder as fans spin up a bit under heavy load, especially if the room is warm.



Mac Pro Mac OS X (10.4.7)

the only time I've heard the fans is when I ran the hardware test, as noted above the only real sound is from the disks.... the superdrive is much noiser than the disks but about the same as one in a laptop such as the MBP