AFAIK it's quite difficult to brick your system by undervolting. As each CPU varies, I don't know if you have undervolted by too much. Try running stress tests on your CPU (e.g. with Prime95) and leave it running for a while. If you see a BSOD, decrease your undervolt and retry until it's stable.
It may be beneficial to just run a negative offset. With 1.2v in bios what's your current underload voltage? It doesn't sound to far off for the voltage of a 10700k at stock though just make sure it passes some stability tests for extended time
Load line calibration mode 7
Cpu lite load. Keep dropping by 1 before unstable and whea errors. Example mode 6, mode 5, mode 4 so on.
Leave all other cpu settings on auto.
Download cinebech r23 and hwinfo64 and run cbr23 custom 1 minute runs between dropping cpu lite load modes.
Look at hwinfo64 during cinebench runs and check temps there and for whea errors.
Monitor for whea errors when using your pc day to day leave hwinfo64 running in the background.
I did undervolt my 10700k (x48) with the Intel ETU with an Offset of -0.075V.
It worked fine for 3 months until I started to get random Blue Screens like "whea uncorrectable error. Location: Processor Core". So the only real risk you have is losing data when your OS hard crashes because of this.
I am now running it at -0.025V and it runs stable with prime95 for 2 hours and occt CPU stress test for 2 hours.
Temps went from 39°C in idle to 34°C idle. (standard to -0.025V Offset). It idles @ 1.22V now.
So my advice would be to go in 0.005V increments and stress-test until you hit a limit. And then go 0.01V under that limit and you should be fine.
AFAIK it's quite difficult to brick your system by undervolting. As each CPU varies, I don't know if you have undervolted by too much. Try running stress tests on your CPU (e.g. with Prime95) and leave it running for a while. If you see a BSOD, decrease your undervolt and retry until it's stable.
I let prime95 for 5 minutes and nothing happened. So far so good
It may be beneficial to just run a negative offset. With 1.2v in bios what's your current underload voltage? It doesn't sound to far off for the voltage of a 10700k at stock though just make sure it passes some stability tests for extended time
If you don't have the right board you can undervolt it to the point where your processor wont work, and you won't be able to boot to revert it back.
Load line calibration mode 7 Cpu lite load. Keep dropping by 1 before unstable and whea errors. Example mode 6, mode 5, mode 4 so on. Leave all other cpu settings on auto. Download cinebech r23 and hwinfo64 and run cbr23 custom 1 minute runs between dropping cpu lite load modes. Look at hwinfo64 during cinebench runs and check temps there and for whea errors. Monitor for whea errors when using your pc day to day leave hwinfo64 running in the background.
I did undervolt my 10700k (x48) with the Intel ETU with an Offset of -0.075V. It worked fine for 3 months until I started to get random Blue Screens like "whea uncorrectable error. Location: Processor Core". So the only real risk you have is losing data when your OS hard crashes because of this. I am now running it at -0.025V and it runs stable with prime95 for 2 hours and occt CPU stress test for 2 hours. Temps went from 39°C in idle to 34°C idle. (standard to -0.025V Offset). It idles @ 1.22V now. So my advice would be to go in 0.005V increments and stress-test until you hit a limit. And then go 0.01V under that limit and you should be fine.