Your Motherboard has Integrated Graphics. In BIOS, do you have the Discrete Graphics as Default? It would look like something like PEG-PCI or something like that in BIOS. If it has IGP or something similar, than the computer is made to boot up with the Integrated Graphics from your Motherboard. If you have PEG as default, then the computer will boot up with the Discrete Graphics (HD 7850).
By your statement it seems like you have BIOS to use the Discrete Graphics. When you boot up with the discrete GPU card, does the computer BEEP more than once while Posting?
When it crashes are there any BSOD error messages or any type of error messages. Did the computer just restart by itself as though you pressed the Restart button on the computer case?
You didn't post your PSU. But if your PSU is equal to or greater than 450 watts than you are fine. Sometimes a failing PSU will cause GPU graphics distortion since it is not getting enough power to operate correctly.
Try installing a previous AMD driver and see if it works correctly. You didn't mention the current version of AMD driver you have installed. By the way, I don't believe you can install AMD Driver set in Safe Mode. Needs to be in Windows Desktop.
Run SFC /scannow in elevated Command Prompt to eliminate any Windows corruption or missing files. to try the following in installing the AMD Driver:
Try this basic method of uninstalling and reinstalling AMD Drivers.
First download the correct Full AMD driver set from AMD Support for your Desktop: Desktop : 3/26/2018 version.
Make sure your Windows 10 is fully updated via Windows Update (including Optionals).
Disconnect the Internet from your computer to prevent it from installing a different GPU Driver than the one you are installing.
Use Windows 10 Uninstall to uninstall all AMD Drivers and software. Then use DDU in safe mode to completely eliminate all traces of the old AMD drivers and software related to the GPU.
Delete C:\AMD Folder. This prevents New and Old AMD driver files from installing and corrupting the installation process.
After rebooting from DDU, Reinstall the new AMD Full set of drivers. If it installed correctly, again delete C:\AMD folder to save Hard Disk space and reconnect to the Internet.
If it the problem continues after everything done here. The best way to check if it is your GPU card is bad is by installing it in another Computer and see if the problem shifts over to the new computer. If it doesn't, than the card is good and you need to find out what is wrong with your computer that is causing the GPU card to not work.
You may want to run a diagnostic test like OCCT which is a free program to Stress test the CPU, GPU, and PSU. Warning: the PSU test can damage or ruin a weak or Cheap PSU. Keep tabs on the Outputs if the PSU test runs and stop it if you see anything strange happening to the PSU.
If you do decide to check your PSU with OCCT and it crashes as soon as the test starts. Download Furmark and use that to stress test the GPU card and see if it crashes. If it does, it is a good chance your PSU is bad or failing under heavy loads.
