Over Voltage errors, Surge detected, Cpu -300°C,... [Asus mb]

Aug 6, 2018

Just 2 months ago graduated from Information Technology High School and I was oftenly troubleshooting someone's else pc. But last few days I find myself in worry with my own PC. I would appreciate an answer or opinion from someone else, as I am not so sure about my decision in solving this problem and I don't want to destroy any of my components.

Problems occured
- 11 days ago I traveled and wasn't home for 8 days. My pc was turned on twice during that by my brother at home (used remote desktop and download some data). But there was problem when he wanted to turn on my pc second time. He had to press the power on button like 10 times before it finally boots up. But it worked fine afterwards. I've always had a problem with power on button and had to press 1-3 times for pc to boot up (but never more than 3 times). I thought that the contacts on top of my case didn't fit properly and it was normal (contacts inside case are fine).
- When I arrived home, I turned on my PC. I had to press power on button like 10 times. Finally, pc turned ON for a sec and then immediately turned OFF and then ON again. Now it showed multiple errors in POST.

1. Power supply surges detected during the previous power on.
2. Asus Anti-Surge was triggered to protect system from unstable power supply unit!
3. CPU Over Voltage Error!

Problems in BIOS

+12V was on 24.480V
+5V was on 10.200V
+3.3V was on 4.080V
and CPU Temperature is -300°C
Nothing changed next day, even after 2 hours of pc being turned on.

Situation before
- 5 weeks ago updated MB BIOS to newest (version 2203) from official Asus site (everything went well)
- 4 weeks ago bought Samsung 970 EVO 250GB NVMe drive and installed official Windows 10 N Education from school license (everything went well)
- 4 weeks ago bought MS office and Kaspersky Internet Security Antivirus from ebay (everything downloaded from official sites and license codes were working)
- Since that, my PC was used only for light tasks (youtube, coding, web development - yarn, git,...) no games or benchmarks or anything heavy

What I have tried
- Took out GPU
- Took out RAM so only 1 remained
- Unplugged both SATA from all 3 drives (was worried about destruction)
- Changing CMOS battery
- Switching between ECO and NORMAL state on PSU (and tried to wait, hold 30sec power on while PSU was unplugged)
- Turn on pc with another power on motherboard pins from another pc
- Turn on pc with another power cable
- Turn on pc in another electrical circuit
- Checked for unscrewed screws and anything that could lead to surge (but nothing founded)
- Cleaned pc and especially PSU from dust (even though I have cleaned it 4 weeks ago) with compressed air
- Unplugged and plugged all MB cables again (everything fits good)
- Unplugged and plugged all PSU cables again (everything fits good)
- I even took out PSU, unplugged it completely from PC, connected PS_ON# with ground pin, and measured Voltage of each output of 24 pin power cable. As a load for PSU I used 2 fans. I had some inaccurate and old measuring digital multimeter but was able to see that 3.3V was 4V, 5V was 5V and 12V was 11V. But it was nothing near what BIOS was showing up!

What I can't / didn't do
- I can't try another PSU or MB (I don't have any extra that would suit my PC)
- I haven't load Windows or any bootable device as I was scared of drives being destroyed
- I can't return MB as the warranty expired

My conclusion
- It looks like PSU is fine, even thought I haven't tested Voltage under heavier load
- MB may went crazy from unknown reason (only software side) but is actualy working
- or MB is not working properly from unknown reason

Additional info
- PSU is whole time plugged into surge protector socket
- I have never overclocked anything
- All overclocking and Voltage is set to auto in BIOS

What I would like to do
- Based on some forums and answers, I would turn off Asus protection (some people said it is garbage) and let pc load and test it with some benchmarks and see if everything works fine. (But it still won't solve my CPU temperature shown in BIOS?)
- Or downgrade BIOS and see if anything is going to change

PC config
Case: NZXT H440
PSU: EVGA SuperNOVA 750 G2 Power Supply 750W
CPU: Intel Core i7-4770k
CPU cooler: Scythe SCMGD-1000 Mugen MAX
RAM: Crucial 4GB DDR3 1600MHz CL8 Ballistix Tactical LP & Kingmax flff65f-c8kl9 4GB DDR3 1333MHz (I am aware of bottleneck & they are not in dual line)
GPU: Asus R9280X-DC2T-3GD5
1. Western Digital WD20EARX 2TB Green Edition (data - photos, videos, games,...)
2. Samsung SSD 850 EVO - 120GB, Basic (empty for now)
3. Samsung 970 EVO 250GB NVMe (for Windows and apps)
Thermal Compound: Arctic Cooling MX-2

Sorry for long post, I've tried to put as much info as I could.
What are your thoughts? Thanks in advance!
I would not trust the asus anti surge software if you are worried about surge then buy a cheap extension lead with that feature but as for a 2015 bios feature turn it off. C P U at 300 no way the motherboard would of shut down way before it reached a 100 find a piece of software.
Aug 6, 2018
It's working! Everything is fine, is stable and I can do same things as before. Except I have to manage CPU fan speed by myself. But that's no problem as my CPU can never get hot even with low speed fan set.


I've turned off CPU temp sensor and Asus anti-surge protection so I could boot PC. Only CPU, MB, 1 RAM and 1 drive with windows were connected to my PSU. Windows loaded. I did benchmarks and everything was fine. So I inserted everything back in case, added GPU, RAM and other 2 drives.

I also had to put jumper into CLRTC [15] (which stands for Clear RTC RAM) and let it be here forever. If I managed to connect it into T_SENSOR[14] PC won't even boot. PC won't even boot if I remove jumper completely. So I let it be connected in CLRTC [15]. (picture below)

+PSU is fine

+RAM is fine

-MB got kind of crazy but is still functionating as it should

-Case power ON button broke

-> I couldn't test another CPU but I hiiighly doubt it would be caused by CPU

What I did

I took out everything from case and let Motherboard be isolated from everything so I had full control. I eliminated all percentages of MB being surged from pc case or laying screws. But MB still showed asus-antisurge etc.

I took out CPU, looked on every pin if it's not bended. Looked if everything is clear. Everything was absolutely fine. MB still showed all errors. Nothing changed.

I've managed to get PSU from working PC and tried it with my setup. Motherboard still showed the same errors even with functionating PSU. It even showed same Voltages. So it was obvious that it was something wrong with MB and not PSU. (I thought from beggining it can't be PSU, like the output Voltage has to change if you disconnect GPU, it would change at least in decimals, even if the PSU would be damaged)

What it probably caused

I found out that my main power on button on case is not working anymore (it's definitely dead and I pressed that button many times). And that destruction may led to why was motherboard showing weird numbers of Voltage. Something probably happend to MB in moment when button died (some surge?). So I had to switch power button with reset button and I am turning on pc with reset button.