Ideal Temperatures Inside mid-2010 27" iMac?

bedouin

I have read many reports of graphics cards in iMacs — particularly 2009 and 2010 models — going bad.

So far I have not had any problems with my machine, but depending on who you talk to, the temperature of my GPU might be a little on the high side (it is driving two displays, though). I really cannot afford any repairs right now, so I'd like to prolong the life of this machine as much as possible.

I've attached a screenshot of what the temperatures look like inside my iMac. If I wanted to lower the temperature of my GPU, what fans might I consider ramping up manually? I live in a hot climate without AC, but try to keep the machine well ventilated and away from sunlight (direct or indirect).

The downside to ramping up the fans (aside from noise) would be more dirt and dust getting sucked into them, and the possibility of one of those dying prematurely. That's still probably a cheaper repair and less of a hassle than procuring a $300 GPU, though.

Marvin

Those temperatures are fine. It's only upwards of 90C that's a problem for a GPU.

http://nvidia.custhelp.com/app/answers/detail/a_id/2752/~/nvidia-gpu-maximum-operating-temperature-and-overheating

bedouin

Thanks for the response.

The GPU in this particular machine is an ATI Radeon HD 5750. I have been told that all mobile Radeon HD cards from the 2009–11 era will inevitably fail, and that the only way to slow that from happening is by ensuring that the GPU remains as cool as possible. Reports online do seem to indicate that the GPUs in these machines do fail pretty frequently.

Marvin

bedouin said:

Thanks for the response.

The GPU in this particular machine is an ATI Radeon HD 5750. I have been told that all mobile Radeon HD cards from the 2009–11 era will inevitably fail, and that the only way to slow that from happening is by ensuring that the GPU remains as cool as possible. Reports online do seem to indicate that the GPUs in these machines do fail pretty frequently.

You can ramp up the fans individually or together to see which combination gives the best temperature reduction for the GPU. Those temperatures aren't anything to worry about though. Even on maximum fan speed, you might only get the GPU down to mid-40C and you wouldn't want to run the fans like that 24/7. GPUs only get hot if you use them for graphics intensive tasks like gaming or computing.

avon b7

These iMacs are thermally challenged. If you live in a hot climate without air conditioning the risk of failure is high IMO. I looked into this when my graphics card failed (late 2009 i7 27inch) and found lots of RadeonHD cases. I spoke to several authorized repair shops who confirmed that they slow cooked themselves over time. Check the grills for dust accumulation. They block very easily and moreso if your heat is humid as the dust becomes sticky.

My machine will only boot into safe mode and I cannot source a new part from Apple where I live. I have seen new parts for sale online in Canada but at over $300. When prices come down I will get one and bring it back from the dead or get it reflowed if I can find someone reputable locally.

Try to clean your vents and keep an eye on the temps.

Mine failed while using Preview. The machine wasn't under any kind of stress at the time but it was the beginning of summer.

Keep your fingers crossed but don't get paranoid over it.

I hope you can avoid this issue.

bedouin

Most of my work involves word processing and research. Over the past few days the weather has been in the mid 30s to low 40s celsius, and the GPU temperature has stayed in the 60s (as shown in the screenshot).

I rarely game, but came across a title last night that I interested me. I checked the GPU temperature after about 30 minutes and saw that it had reached 80-something degrees. I was a bit surprised that the iMac's firmware did not ramp up the fans substantially to bring that number down a bit. I manually increased the speed of all three fans by a little over 50% and managed to get the temperature down to the mid-40s — even while gaming.

Since the iMac is not particularly aggressive about keeping things cool, I can see how certain types of users would have GPU failures very quickly. From now on I will keep my eye on the GPU temperature whenever I am doing any graphics intensive tasks. I have also started putting the computer to sleep more often when I am not using it. For years I always believed that the sleep-wake process was harder on machines than merely letting them run nonstop, but perhaps the nature of electronics has changed somewhat in the past 20 or so years.

avon b7 said:

My machine will only boot into safe mode and I cannot source a new part from Apple where I live. I have seen new parts for sale online in Canada but at over $300. When prices come down I will get one and bring it back from the dead or get it reflowed if I can find someone reputable locally.

Can your machine be put into target display mode in its current state?

avon b7

bedouin said:

Most of my work involves word processing and research. Over the past few days the weather has been in the mid 30s to low 40s celsius, and the GPU temperature has stayed in the 60s (as shown in the screenshot).

I rarely game, but came across a title last night that I interested me. I checked the GPU temperature after about 30 minutes and saw that it had reached 80-something degrees. I was a bit surprised that the iMac's firmware did not ramp up the fans substantially to bring that number down a bit. I manually increased the speed of all three fans by a little over 50% and managed to get the temperature down to the mid-40s — even while gaming.

Since the iMac is not particularly aggressive about keeping things cool, I can see how certain types of users would have GPU failures very quickly. From now on I will keep my eye on the GPU temperature whenever I am doing any graphics intensive tasks. I have also started putting the computer to sleep more often when I am not using it. For years I always believed that the sleep-wake process was harder on machines than merely letting them run nonstop, but perhaps the nature of electronics has changed somewhat in the past 20 or so years.

avon b7 said:

My machine will only boot into safe mode and I cannot source a new part from Apple where I live. I have seen new parts for sale online in Canada but at over $300. When prices come down I will get one and bring it back from the dead or get it reflowed if I can find someone reputable locally.

Can your machine be put into target display mode in its current state?

I haven't actually tried it as all my data is accessible from backups. That said, booting via TDM wouldn't remove the vertical bars caused by the failed graphics card so I prefer to use a MBP.

Remember that it's not only applications that you would expect to push the machine hard that can be problems. Depending on your system, use etc something as stupid as a runaway Flash process can wreak havoc and send temperatures into overdrive.

bedouin

You're right, I have a CPU meter in my menu bar and the Monity widget to keep an eye on temperatures and fan speeds. If I see the CPU usage jump beyond about 25% I become suspicious and begin to investiage things.

I'm not entirely sure how target display mode works, but the graphics card might actually be bypassed once target display mode is invoked. A guy I once chatted with said his GPU was completely fried but that he was still able to use his iMac as an external display for another machine.