Hello, I'm having this frustrating issue with my PC and I can't find any solution. I hope some of you guys can help. Few days ago I've got this message on the screen right after turning on the PC: UEFI date/time not set, press F2 to setup, F1 to continue. So googling around I've find what seemed to be the solution, that is change the CMOS battery. Then when I restarted, this message was replaced by this one: UEFI defaults have been loaded, press F2 to setup, F1 to continue. Since then I'm not able to start the PC without getting this message and more important I can't save any UEFI. This would happen ONLY if I also unplug the power cord. If I just shut down the system and leaving the power cord plugged in, the system boot up normally. By pressing F1 I can get to Windows and the system seems to run smooth, without any problem. CPU temps are normal, RAM get detected normally, SSD and HDD works, everything seems fine. I tried pretty much everything to solve the problem and I followed similar posts but without any luck. This is what I've tried so far: CMOS reset with jumpers (few times) and by removing the battery, changed the old battery with a new one and tested both with a voltmeter (both 2,9V pretty much), clean the battery holder with alcohol and by rubbing the contacts, disconnect any peripherals device, flashing the UEFI with the new update (2.00) and even the older ones (1.80,1.90), changed UEFI settings, reinstalled Windows 10 three times and changed between Home and Pro versions, updated all the drivers, disabled all the USB ports, removed the MB from the case, cleaned all the parts and mounted it back, even changed thermal paste.. As you can see this is driving me crazy!!!Please help! These are my specs: MB: ASRock H97 Pro4 CPU: Intel 15 4440 RAM: 2x4GB HyperX Fury Black DDR3 GPU: Onboard graphics (atm because I'm waiting for the new ones) SSD: Samsung Evo 250 GB Sata III HDD: WD Caviar Blue 1TB PSU: Enermax Triathlor ECO 550W MONITOR: AOC g2460pf (this info is probably useless but all this started because I needed to install beta drivers for it and had to reinstall Windows 10 to do that) I apologize for my poor English but it isn't my native language. Thanks in advance.