MP 1,1-5,1 PCI fan speed issue

Ih8reno

macrumors 65816
Original poster
Aug 10, 2012
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I have a 5,1 with a flashed gtx 680 for a gpu. When the computer is running the card works great boot screens and all. Only thing is the pci fan speed is set around 1600rpm and goes up fast when video is on. I can’t find any temp readings from this card and wanted to get your opinions. Should I simply use Mac fan control and set the pci fan at temperature ambient readings for 30c base at 800 rpm and to go up at 39c to ramp up? Or is there some other way to de stress this fan. Or finally is it normal it’s this high and should I leave the pci fan alone.
 

skizzo

macrumors regular
Apr 11, 2018
246
76
800 RPM is the default speed it runs and ramps up accordingly by temp (I assume by ambient PCIe area temp). you're stating it's "set" around 1600, you would need an app like MacsFanControl in order to control it in such a way. which if you are doing that, just lower the settings. it's a basic adjustment
 

Ih8reno

macrumors 65816
Original poster
Aug 10, 2012
1,342
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Thank you, I am using the app. My question is what’s the best thing to do. Adjust the fan by default to certain settings, or go by ambient temps as it gives me the option to do. I know these old GPUs can get toasty so I don’t want to set it to a speed where fresh air isn’t being sent to it.
 

skizzo

macrumors regular
Apr 11, 2018
246
76
Thank you, I am using the app. My question is what’s the best thing to do. Adjust the fan by default to certain settings, or go by ambient temps as it gives me the option to do. I know these old GPUs can get toasty so I don’t want to set it to a speed where fresh air isn’t being sent to it.
specific temps will be best decided by yourself dependent on a few things, mainly how loud/fast you want the fans and what temps you wish to maintain. I can recommend using particular temp readings for particular fans. the PCI fan would best be controlled by the PCIe Ambient Temp, especially if you have an open air design GPU. if its a blower GPU not as much hot air will be in the PCIe area so the ambient temp will be lower likely. temp settings will need to be lower to achieve same fan speeds when comparing a blower to a open air gpu

if you're referring to adjusting the fan by default to certain speed, avoid that at all costs. that sounds like you're talking about a fixed speed which is perhaps desirable at times but if you're concerned about temps and longevity, you would be putting your GPU at risk of overheating due to a fixed speed setting would not ramp up in the situation of a GPU getting hotter than normal. best case scenario is the GPU would run hotter than average, worst case is it's going to overheat and shutdown your system more frequent
 

Ih8reno

macrumors 65816
Original poster
Aug 10, 2012
1,342
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Thanks for the responses. I set the fan to ambient 34 /60. There are no drives on the sleds and just a gpu and PCIe ssd plus my USB card in the mac. Fans are much quieter. Going to leave it like this for a week or so and if no issues I think it’s the sweet spot!