GPU Going bad

Hello everyone first and foremost thanks for reading. Now the problem, I recently bought a custom made PC from Digital Storm, It came with the MSI 1080 TI aero OC gpu which I heard has heating problems, I ordered mines with some extra fans and with a non maintenance AIO. everything was good for the first 3 weeks, GPU was Overclocking and giving me 1986MHz, with a +50 on afterburner, that is how it came. all was good, recently i started getting some very bad artifacts on final fantasy 14, so I dial back the clock to +25, still show artifacts, I dialed it back to -50 and the artifacts stopped, for Ff14 and other games, now the artifacts came back, for witcher 3 and all my other games, so I dial back to -100, all was good, now a week later, Im staring to notice small artifacts on witcher 3. Whats going on? I keep dialing back and the artifacts keep coming back as well, the PC started with +50 just fine on a max of 1986Mhz, now Im on -100, 1896Mhz and getting artifacts again. do I have a bad GPU?


Full Specs:
CPU: AMD 2700x @3.7Ghz
GPU: MSI 1080Ti Aero 11GB OC
Ram: 16GB (8x2) 3000mhz
Motherboard: Asus Prime x470
Power Supply: Corsair 750Watt

Not high at all, OC 1080 Ti are on average higher than 1900Mhz, with many reaching 2000Mhz+, mines was fine at 1986 before, but now as I underclock the artifacts follow eventually, its a clear sign the GPU is dying. Buts its a brand new gpu badically, this machine is not even a month old.