I have been using DZ87KLT-75K mother board for past more than a year without any issue until last weekend when I upgraded the processor from i5 4670 to i7 4790k.
Here is my system configuration,
Motherboard : DZ87KLT-75K
Processor : Core i7 4790k (Previously it was Core i5 4670 )
RAM : Corsair 2x 8 GB DDR3 1600 MHz
PSU : Cooler Master V1200
GPU : 1x Asus AMD Radeon 280x + 1x Asus AMD Radeon 290
HDD : 3x WD Purple 4 TB
OS : Win 8.1 Pro 64x with UEFI BIOS
When I upgraded the processor from i5 to i7, I formatted my primary HDD & installed fresh copy of Win 8.1 Pro straight (without booting from old OS)
Since I want to use 4 TB HDD, I've selected UEFI Boot drive option & disabled legacy boot option under bios.
Win 8.1 installed smoothly without any error but surprisingly after completion of installation on first "RESTART" my system just stuck with debug code showing "00 00" & all system fans still running !
I must switch off my PSU & manually start the system there after every time whenever the system needs a restart, whether it's after installing certain drivers or updating OS from Microsoft !
Everything else works fine just whenever I press restart button, the system sticks to debug code "00 00" with all system fans running !
After searching for this issue on the web I finally decided to update my BIOS from 0451 to 0453 which was done successfully but after that BIOS update, got a new issue (RESTART problem was not solved)
Now whenever my system boots, it gives 2 beeps twice with a pause in between i.e. "beep" "beep" _pause_ "beep" "beep" then it boots normally, but still restart problem is there.
I have noticed that after BIOS update the "Video LED" remains off on the board indicators.
One thing is worth noting, that I mostly use this system headless via team viewer from my work so there is no screen attached to it.
But when I attach screen via HDMI port of my GPU, I don't get those beeps (However the video LED still remains off)
So now I have 2 issues,
01. My system can't be restarted. I must shut down & start manually.
02. 2 beeps twice on every boot with Video LED remains off.
Please help me to rectify this issue.
Concerning your first problem, the issue is the i7-4790K, just to be clear the CPU it self is not bad,.. Intel decided to thew us loyal customers under the bus on the haswell refresh by deliberately not releasing a BIOS that supports the haswell refresh, when asked about it they say its coz they are no longer in the business of producing desktop boards, so sorry buddy unless Intel changes their mind which is unlikely, you will have to purchase/exchange your CPU for any other 4th CPU before the refresh, check compatible CPU list for the board. I am pissed off too about this fiasco.
Second problem is what I'm curious with coz i have just checked my PC and to my surprise that video LED is off, should it be like this INTEL answer!!!!???