Shutting down during a stress event usually points to a weak power supply.

hi Puffnstuff and sparax , thxs for your reply's.

Puffnstuff: i don't think that power supply cause the mistake, please look at my PC Specs. I have an OCZ Fatality 750 watt power supply installed. Only one grafic-card called GTX 770 is in the pci-e slot. My calculation says that i have enough reserves. two HDD, two SSD, one Optical drive, one grafic-card, two 8GB Ram DDR3 and the CPU. Please tell me, whats wrong.

Sparax: i can and i do now the Memtest , but i think it's not the RAM, they run at 2133 Mhz with the XMP profile. Than i look the Eventvwr.msc for events.
The BIOS version 2201 is only that i don't need update for my I7-4790K , it's only when you install the fifth Generation CPU (i5-5320 example) , i don't hope that afteBios update the complete PC runs a little bit more unpalatable than now.

Set your RAM to the default speed and test again, even though it is capable of the XMP speed that is still considered an overclock, if it does not crash with the Ram at default then enable XMP profile again and add a little extra voltage to your RAM, .02 volts would be a good start

A fatal shutdown during a system stress test usually points to a faulty or defective PSU.
Pull the GTX 770 from your PC and use on the onboard video furnished by your i7 4790k.
Run the same test again and see if you can get through the benchmark without a crash.

hi menthol and nemesischild , THXS!
News: i have let the RAM at XMP (2133 mhz) and done the memtest86+ with two Passes, Result= no errors , by 2 Passes. =RAM is good.
befor i make the next steps: Which effect has the update for the BIOS now ,when i do from Version 2201 to Version 2702 to my system? should i do
this for my CPU I7-4790K? What brings it?

A bios update will wipe out all previous settings, I always clear the CMOS before and afterwards.

Nothing more is really needed, just make note of your oc settings before doing the update.

Thxs NemesisChild for your fast reply,
OC-settings never be made, because the i7-4790K runs on normaly mode with 4Ghz default and 4,4Ghz Turbo Boost, CPU drives between 800 Mhz and
4000 Mhz, in moment i don't need to push cpu. the only thing or hardware that runs higher is the RAM (2x 8 GB) instead default they go at 2133 Mhz.
For me it's clear that all settings in Bios were gone,when i update it. the last 2 hours i have set the FAN settings new.
The Shutting-Down-Crash (this Thread) can also caused , i think, from the heating CPU, i found out. For 25 seconds i start the stability-test to stress
cpu and i have seen that three from four cores are over the TDP Temp point.
Then i have carves the Tower, to put the cooler from cpu, set bigger Fan on the top to cpu, cleans the old conductive paste and take new. In Bios i set
the new FAN setting.
I can wait now, if the shutting down crash comes again or the problem is now gone.
Bios update to 2702: Never touch a running system ! ----> i only made it, when everything not running.

i'm back after long time and send greetings to all.
News: i have changed cpu cooler --> enermax liqmax ii 240 , while cpu would be to hot for me.
the problem of shut down is actually present at this time. from all reasons or components they can cause this issue , i localize only two components.
Motherboard VII hero or the CPU.
I'm afraid to update the Bios and after it's the same as before