Resolved ATI Radeon HD 5770 in Mac Pro 4.1 NOISE

[jenzjen]

Here's my general findings with fans and several different cards; this is a 5,1 machine with 3 27" Apple displays.

OEM 5870 (slot 1) + OEM 5770 (slot 2, powered via splitter from one of the power cords heading to the 5870) - fans were never an issue in either OS or Windows as long as the brightness wasn't set too high. Max brightness spooled fans in either OS, which makes sense given the power needed to drive all those pixels.

Now non-OEM 7870 in slot 2 using both 6 pin adapters. Fans run around 1100rpm only following a shutdown and start-up, but the more I sleep and wake the machine, the fans settle back down to the normal "quiet" 600-700 rpm. The fans stay "quiet" even if I restart between OS and Windows as long as I don't do a shutdown then restart.

Strangely, this card in slot 1 exhibited much more erratic fan behavior. Speeds after a shutdown would be around 1500rpm, would randomly boost higher/lower and never settled back down to "quiet" speeds hence why my GPU now lives in slot 2.

Note, after each time that the card was moved into a new slot, I did a PRAM and SMC reset.

 

[grame]

Do you have an Apple OEM 5770? Are you using a Mac Pro 5,1 or 4,1 (or other)?
I would not have expected your PCI fan speeds to fluctuate like that in Slot 2. But, if you are using a 'supported' card, then perhaps Apple insist you have it in Slot 1.
I use an unsupported card, so I see odd fan behavior in Slot 1, but not in Slot 2.
Another Forum Member (Actionable Mango, I think) mentioned in another thread that this is known phenomenom. Unsupported cards will produce odd fan behavors in SLot 1, but you can get around that with certain 'tricks'. One trick is using Slot 2. The other is stressing the GPU with a benchmark so the PCI fan throttles back down to a steady 800 rpms.
The Stress-test trick does not survive a reboot, however, and you PCI fan will start fluctuating again.

In the end, I just returned the GTX 650 to Slot 2 where fanspeed is predictable and steady. It blocks access to SLot 3, but I've got no other cards in there.

I forgot to mention that Mango stated that some users of Mac Pro 4,1 have reported the fanspeed fluctuations with an Apple 5770 (which is not 'officially' supported on that model Mac Pro).

Mine is a brand new genuine Apple 5770 on a 4.1 Mac Pro running on the 5.1 firmware upgrade.

I guess I will just need to do the stress test thing when I boot up. Which is a bit boring.

 

[pastrychef]

the more I sleep and wake the machine, the fans settle back down to the normal "quiet" 600-700 rpm.

Wow. I don't think I've ever seen the expansion slot fan that low. I'm jealous.

 

[Studio K]

OEM 5870 (slot 1) + OEM 5770 (slot 2, powered via splitter from one of the power cords heading to the 5870) -

I did not know you could do that. I'll bet Apple would not approve.

Now non-OEM 7870 in slot 2 using both 6 pin adapters. Fans run around 1100rpm only following a shutdown and start-up. Strangely, this card in slot 1 exhibited much more erratic fan behavior. Speeds after a shutdown would be around 1500rpm, would randomly boost higher/lower and never settled back down to "quiet" speeds hence why my GPU now lives in slot 2.

Your experience with your 7870 seems similar to that of the Thread Starter, who was using a 5770 in a 4,1.

Thanks for posting your experiences.

the fans settle back down to the normal "quiet" 600-700 rpm.

I did not think that the PCI fan was 'permitted' by the SMC to spin that slowly. I've never seen it below 799.

 

[jenzjen]

I did not think that the PCI fan was 'permitted' by the SMC to spin that slowly. I've never seen it below 799.

I could be wrong, my memory remembered 6XXrpm or 7XXrpm but easily could be 8XXrpm. The only things that I can remember with certainty are that it was under 900 and 7870 once "settled" would be same speed as the OEM 5870 running bone stock. Sorry for any confusion.

 

[Studio K]

I could be wrong, my memory remembered 6XXrpm or 7XXrpm but easily could be 8XXrpm. The only things that I can remember with certainty are that it was under 900 and 7870 once "settled" would be same speed as the OEM 5870 running bone stock. Sorry for any confusion.

I've got iStat installed and placed some of the fan speeds in the Desktop's menu bar. They are big and bold and update every few seconds, so it's easy to spot any unusual behavior.
I set that up awhile ago to monitor BOOST (cpu) fan just after I swapped CPUs.
It's a nice way to effortlessly keep an eye on things.

 

[Macsonic]

My PCI Fan Speeds averages 799rpm to 850rpm. I have a GTX285 on my 3.1 Mac Pro, a Radeon 5870HD on my 4.1 Mac Pro, all Mac editions. I just sold my Radeon 5770HD Apple oem. I don't seem to recall my PCI fan speed going at 900rpm or above.

 

[Fastsavage]

OK done some swapping of cards (GT120 and HD5770) and here are my findings...

B1, B2, Exhaust, PCI, Intake, Power Supply

GT120 in Slot 1 all fan speeds "normal" 1113 1113 600 800 600 600, stressing the card doesn't make it change much.

HD5770 Slot 1 1113 1113 600 1800 600 1120 stressing card put PCI to 2100 and the rest pretty mush the same

HD5770 Slot 2 1113 1114 600 1009 599 629

Both cards (GT120 in 1 and HD5770 in 2) 1113 1113 600 1130 600 705

Heres the thing though - I notice that the PCIE slot 1 temp is 40 with the GT120 card in and 129 with the HD5770 in, so the SLOT sensor itself does't work with the HD5770 in?

I'm sure someone more knowledgeable than me can throw some light on this finding.... I hope.....

Cheers

 

[slughead]

Heres the thing though - I notice that the PCIE slot 1 temp is 40 with the GT120 card in and 129 with the HD5770 in, so the SLOT sensor itself does't work with the HD5770 in?

I think that may be my problem as well... the temperature I'm getting doesn't make any sense.

Although I'm getting around 50 while idle which is at least realistic, not 129 (sweet je**s!)... are you sure you're not switching from C to F?

here is my post in another thread about this issue and how I got my RPM down.

 

[Mac Hammer Fan]

I assume Apple wouldn't recommend the card at all; Apple's requirements for the 5770 are 5,1 and newer, whereas OP has a 4,1.

Strangely enough, Apple's requirements for the Apple 5870 are 4,1 and newer.

That being said, people have used them without the fan problem on all models of the MP.

Not me. I had the fan noise problem with the 5770 on my MacPro 2009 and I returned the card. I bought the 5870 instead and this one is silent. (800 rpm)

 

[Fastsavage]

I think that may be my problem as well... the temperature I'm getting doesn't make any sense.

Although I'm getting around 50 while idle which is at least realistic, not 129 (sweet je**s!)... are you sure you're not switching from C to F?

here is my post in another thread about this issue and how I got my RPM down.

Yip sure its C but 129 is the default when the sensor isn't found / available so temp not really that !

Noise doesn't bother me now I guess I'm used to it and is only 40 db while sitting at my desk, but I will look at the app you recommend

Thanks

 

[ubuntunerd]

I just found this very informative thread !!!
I had same issue mac pro 2009 4 core ATI radeon 5770 apple edition was running great, after i shot down the computer to upgrade to 32 g ram the PCI and PS fans when up to 1800 rpm but after reading about the stress test and running it the speeds are back down to PCI-799 PS- 600

weird behavior for sure I only notice because I have never heard the fans on this mac till today is always quiet !!