I have finally been able to test the GPU cooling system efficiency!
OCCT 5.4.1 has been used again, this time with the GPU 3D Shader3 test.
Here under some results:
As you can see, somme thermal throttling occured after less than 10 minutes of load.
With a core voltage of 1.19V, the GTX760 temp rised up till the limit value of 81°C.
To stay under that limit, the core voltage was (automatically) reduced to around 1.1V, which corresponds to 75% of the GPU power.
According to Asus (https://www.asus.com/Graphics-Cards/GTX760DC22GD5/specifications/), the TDP of this GTX760 Direct CU2 is 225W.
So while my early calculations were aiming at cooling a power of 175W, the system right now is able to keep 169W (225W x 0.75) below 80°C.
Quite good I would say, even without the help of an additional vapour chamber! \o/
Temp probes were also attached to the system, but the one on the copper block ended up being defective. The block being not easily reachable, I launched the test without replacing it.
A working temp probe was attached to top of the aluminium heatsink though, showing a max value of 54°C.
That makes a temperature delta of 27°C (81-54) between the GPU core temp and the top of the heatsink.
On the CPU side, the same kind of measurement showed a delta T° of 64°C (95-31), which again seems to point at a bad heat transfer from the CPU die to the heatsink.
Just to check, now that both sides are up and running, I redid the GPU test while the CPU was performing a Large Data Set benchmark on another OCCT. The results were totally similar, which means one side of the case doesn't influence the other side. Good thing!
I am already happy of what have been achieved on the GPU side, but let's see next if all this can be improved with the use of some vapour chambers!
