Unity 5 and games cause violent fan noise and black screen...

I'm experiencing a big issue with Unity 5 since I installed my PC configuration in a tower ; before experiencing this issue, my Motherboard was simply set on my desk, and I could use my computer like this without problems for many months until today ; but I think this is not the cause of the issue.

Using Unity 5 for a few minutes now causes a sudden and violent GPU overheat followed by a video signal shutdown.

According to Open Hardware Monitor software, the GPU temperaure increases by 1 degree every 3 seconds using Unity 5 in Play mode in a mostly empty scene with a directional light, which doesn't seem normal.

Verifying if the problem really came using Unity, I left the software running in Play mode in the same scene until the GPU temperature reached 66 degrees, because I feared it would go too high like this. I then closed Unity, opened it a second time later, and my GPU fan (I guess, the noise is too loud to know where it comes from) instantly made a violent vaccum noise followed by a video signal loss once again. It happened 4 times today.

I have actually no problem using Blender rendering a + 6 millions tris mesh using SSS material. The GPU temperature reaches 45 degrees max in Render mode with this model.

Side note : on Open Hardware Monitor, I see there is something which temprature reaches a constant 125° and I dont know what that is : | | +- Temperature #3 : 124.5 123.5 124.5 (/lpc/nct6791d/temperature/3)

Here's the GPU statistics in idle mode :

| +- GPU Core : 139 139 1506 (/nvidiagpu/0/clock/0)

| +- GPU Memory : 405 405 4006.8 (/nvidiagpu/0/clock/1)

| +- GPU Shader : 278 278 3012 (/nvidiagpu/0/clock/2)

| +- GPU Core : 31 28 34 (/nvidiagpu/0/temperature/0)

| +- GPU Core : 0 0 20 (/nvidiagpu/0/load/0)

| +- GPU Memory Controller : 2 1 15 (/nvidiagpu/0/load/1)

| +- GPU Video Engine : 0 0 0 (/nvidiagpu/0/load/2)

| +- GPU Memory : 7.24058 5.74875 7.45392 (/nvidiagpu/0/load/3)

| +- GPU : 1099 1089 1109 (/nvidiagpu/0/fan/0)

| +- GPU Fan : 27 27 27 (/nvidiagpu/0/control/0)

| +- GPU Memory Free : 7598.85 7581.38 7721.06 (/nvidiagpu/0/smalldata/1)

| +- GPU Memory Used : 593.148 470.938 610.625 (/nvidiagpu/0/smalldata/2)

| +- GPU Memory Total : 8192 8192 8192 (/nvidiagpu/0/smalldata/3)

I don't know what's happening and I would need some clues about this issue.

My Configuration

Motherboard : ASUS X99 A II

Graphic Card : ZOTAC GTX 1070 8 Go

Processor : Intel Xeon E5 2683v3 14 Cores 2.00 Ghz

CPU Fan : Noctua NH-D15S

Here's a picture of it :