3 ms·

>That said I’ve been out of the PC space for quite a while. Do mobile discrete GPUs greatly draw much power when mostly idle (such as general desktop work)? Did

by apohn 5y ago

>That said I’ve been out of the PC space for quite a while. Do mobile discrete GPUs greatly draw much power when mostly idle (such as general desktop work)? Did others give up on switching the discrete GPU on and off a needed as Apple used to do (and gave up on IIRC)? I recently purchased and returned a Lenovo P1 Extreme Gen 4. It had an 11th generation i9 and a 3080. With no external monitor attached, the 3080 power consumption in HWinfo was 0 watts doing basic tasks (e.g. surfing HN).This was plugged in or on battery. If I plugged in an external 4K monitor, the 3080 power consumption was ~23 watts. A few watts less with a 1080 monitor. I think 27W if both were plugged in. I think a lot of laptops can basically turn off the discrete GPU when it's not being used. Not sure about gaming laptops. There's some quirkiness to this with the GPU not turning always turning off when you unplug an external monitor - a reboot is required.

MBCook 5y ago
Thanks for the numbers. I’m glad to hear it can turn off, but I will say I’m surprised it’s minimum draw is so high when it’s on.
- apohn 5y ago
  In hindsight, one of the thing I didn't check was the GPU draw at idle (with a monitor plugged in) when the laptop was in Balanced Power mode. Typically if I plugged a monitor in I also had the power cord in. And with the Power plugged in, I had the laptop set to highest performance mode in Windows. There is a balanced mode which is more conservative with power consumption. I wonder if the GPU idle draw would have been lower. The laptop I used also had the external TB4/USB-C and HDMI ports wired to the NVIDIA GPU. This means that external monitor = GPU on. I wonder if there are some laptops that can use the iGPU for basic tasks, and only switch to GPU as needed. There are also laptops with less powerful discrete GPUs that might draw less power at idle.

by apohn 5y ago

MBCook 5y ago

Thanks for the numbers. I’m glad to hear it can turn off, but I will say I’m surprised it’s minimum draw is so high when it’s on.

apohn 5y ago
In hindsight, one of the thing I didn't check was the GPU draw at idle (with a monitor plugged in) when the laptop was in Balanced Power mode. Typically if I plugged a monitor in I also had the power cord in. And with the Power plugged in, I had the laptop set to highest performance mode in Windows. There is a balanced mode which is more conservative with power consumption. I wonder if the GPU idle draw would have been lower. The laptop I used also had the external TB4/USB-C and HDMI ports wired to the NVIDIA GPU. This means that external monitor = GPU on. I wonder if there are some laptops that can use the iGPU for basic tasks, and only switch to GPU as needed. There are also laptops with less powerful discrete GPUs that might draw less power at idle.