Mac Pro 4,1 CPU fans go nuts when opening a game in Bootcamp / Win 7

[Finndamage]

Hi all,

I recently bought a Mac Pro 4,1 (Eight Core 2.26 Nehalem / Early 2009) which I then firmware upgraded to 5,1. I invested in a Sapphire Radeon HD 7950 Mac Edition. My purpose is to use OS X for photo and video editing and Windows 7 for occasional gaming.

I installed Windows 7 in Bootcamp, installed the GPU drivers for Windows and set up my favorite game, World of Tanks. The performance of the Mac Pro and the GPU should be more than enough.

I was amazed to hear the CPU fans to start running very loud instantly when the game was opened (in the garage view, not even actually playing yet).

The second I either hide/minimize the game or close it, the fans instantly quiet down.

I tried SMC reset and also checked that there's no dust inside the Mac Pro. I can't believe there's nothing to be done with the fans but I'm running out of ideas.

So, is there anything I can try or do I just have to accept that my Mac Pro runs awfully loud when just opening a game? Fortunately it doesn't get any worse when actually playing. I suppose it just can't..

 

[h9826790]

It sounds like your graphic card's fan noise, but not the CPU fan's noise.

You may run Furmark to stress your GPU, and use GPU-Z to monitor your fan speed. Then check if the noise is the same as when your play games.

The HD7950 Mac Edition card is quite noisy when under load. If that's the problem, you can use Afterburner to lower the core voltage (0.975V works quit well), and hard tune the fans speed at around 31%. This will keep your card cool enough but with much less (and constant) fan noise under Windows.

 

[Finndamage]

Thanks for the quick reply!

I'm quite sure it's the CPU fans but I will check your suggestions later today.

 

[AppleDroid]

Thanks for the quick reply!

I'm quite sure it's the CPU fans but I will check your suggestions later today.

My 2009 Quad heats up quickly using bootcamp, even idle. What i've done is log into OSX, use SmcFanControl to crank my fans defaults up, then without shutting down reboot into Windows.

Otherwise the fans never ramp up no matter what I do and my temps hit their thermal limit within 30 minutes of gaming.

 

[h9826790]

Otherwise the fans never ramp up no matter what I do

Yeah, this is normal. That's why I think his fan noise problem is coming from the graphic card rather than the CPU fan.

The CPU fan should be too quiet but not too noisy.

 

[Finndamage]

Oh yes, it was indeed the GPU fan. I can't believe I was that wrong.

Thanks for the Afterburner tip. With it the noise is acceptable although I'm still amazed how loud the GPU really is.

 

[h9826790]

With it the noise is acceptable although I'm still amazed how loud the GPU really is.

You can actually build your own fan profile in afterburner to make it more quiet, the 31% fixed fan speed is very safe for that voltage even under full load, but that's still a little bit noisy. If you have no plan to OC the card, you may further lower the voltage to somewhere like 0.963V. And keep the fan speed below 29%.

 

[Finndamage]

You can actually build your own fan profile in afterburner to make it more quiet, the 31% fixed fan speed is very safe for that voltage even under full load, but that's still a little bit noisy. If you have no plan to OC the card, you may further lower the voltage to somewhere like 0.963V. And keep the fan speed below 29%.

Thanks for the tip. I will definitely give it a try and see how well it performs in gaming and how stable it is.

 

[haralds]

Thanks for the tip. I will definitely give it a try and see how well it performs in gaming and how stable it is.

Generally, the graphics card fan comes on for a purpose: the GPU might be getting hot!
I would live with the noise and not jeopardize the life of the card...

Is it possible, the game is cranking the fan to prevent issues?

 

[Finndamage]

Generally, the graphics card fan comes on for a purpose: the GPU might be getting hot!
I would live with the noise and not jeopardize the life of the card...

Is it possible, the game is cranking the fan to prevent issues?

Well, if the noise is at acceptable level and the temps remain below 70°C even when gaming, I'd say it's OK.