Weird Gpu Load and Power

[Verang]

I was recently stress testing my GPU with MSI Kombuster and the GPU runs perfectly fine alone. But when I added OCCT or Aida64 alongside Kombuster, the GPU would drop in its usage percent and its power percent (seen through MSI Afterburner). What is the problem with this GPU load and power delivery?

My system was slightly overclocked but I ran everything at stock settings to rule out that factor, but was still getting the problems. The temperatures were also fine.

My system:
CPU: 3570k at stock

GPU: MSI 660 ti power edition at stock

PSU: Seasonic ss-750km3 750w

Motherboard: Gigabyte GA-Z77X-UD5H

 

 

 

Edit: The reason I wanted to stress both was because I thought my GPU was unstable due to some crashes with the driver (314.22) while playing games.

I have also read that people usually only stress CPU/GPU seperately. Is there a problem with stressing both at the same time?

[piplupgao]

try updating drivers

[Elbstrand]

I think it's because you can't max out both at same time, just because stress testing graphics also uses some CPU. When you overload the CPU to a point where it can't really communicate with the PCI-E lanes anymore, your graphics power will drop.

[Godlygamer23]

3570K at stock shouldn't bottleneck a 660 Ti. Does the same thing occur when playing a game without Vsync?