56whr Precision 5520 Owners: Observed Battery Life?

I believe the components don't share the same caps/mosfets so GPU load shouldn't affect anything. It's not heat radiating from the GPU that causes it - it's the lack of cooling on the VRM modules from what I've read.

 

The dissipation of any heat within the VRMs will be influenced by the temperature of the environment they are in. As the inside of the chassis heats up, which will be worse with combined CPU + dGPU loading, radiation and conduction of heat from the VRMs will reduce and they will get hotter. A further factor is ambient temperature which affects the both the coooling air temperature and radiation from the outside of the notebook. I wouldn't be surprised if Dell's development labs are air-conditioned to a lower temperature than many users homes (particularly during summer) so cooling systems which are adequate in the laboratory aren't OK in some real life conditions.

John

 

Yeah, you make a very good point. The machines are usually validated for 22*C ambient operation, though most people use them at 25-30*C.