First of all, provide FULL PC specs. Which GPU model/brand is it ?? What's the exact TEMP value in IDLE mode ? And what about the GPU usage and load in idle mode ? Do you have any BITCOIN MINING VIRUS on your system by any chance ? Scan your PC by using any AV/anti-malware software.
Are you using a FRESH installed copy of Windows OS ? Can you restore back your OS to some other point ? Also, I assume all your system files, device drivers, firmware and BIOS are fully updated ??
You might be getting this error, ""Application has been blocked from accessing Graphics hardware"", which could happen if the OS files are either corrupt, missing, and/or damaged. But there are few other causes as well. For the time being, try running the "System File Checker" and the 'DISM' Windows commands
Type cmd in the search box. Then right-click on Command Prompt to select Run as administrator. Click YES if prompted by a User Account Control/UAC Window. Then Type sfc /scannow and press Enter. Wait for the scanning to be 100% completed.
After that, type the following commands and press the Enter key.
DISM.exe /Online /Cleanup-image /Scanhealth (This command scans for component store corruption, but does not correct any issues).
DISM.exe /Online /Cleanup-image /Restorehealth (The /RestoreHealth parameter runs a scan for corruption and attempts to repair any issues that it finds automatically).
Restart your OS after doing all this. I would also recommend scanning the REGISTRY for any corrupt/missing entries. If the issue persists, then we need to check the Hardware, or look for some other solution. Is that a brand NEW card ? There are few more tips to help resolve this issue which you are facing. But from the distorted image which you have posted above, it looks your GPU might be having some fault as well.
Doing a CLEAN and a fresh OS install won't hurt either. But keep this as a last resort.