Fps issues, please no redirect to old forum, ive been there not a solution

Hi, how can it be, that I have a pc with a i7 9700k, an rtx 2070, and I get sometimes 300 perfect FPS, then by chance 200 or even less.
No overheats, no issues due to running background things, my ram is 3200MhZ 16 GB, so no problems there also. I have a SDD 860 evo Samsung + an HDD both 1 tb each, all installed on the SDD.
I have not power serttings, neither nvidia settings on low, all high performance mode ON.
Graphics set to low, render to 100%, everything already said in forums or else ive been doing it.
I dont even know what else can I do, my cpu is water cooled by a corsair H100 series, no way that is problem, My gpu never goes above 75º no matter how hard/long I punish it, It normally on overwatch runs at high 60s or low 70s, Is anyone else having this frustration ?
It is not nice at all to be at 300 then drops to 200 sometimes, you tell your self that stills fine, but when it drops under 150 I just want to cry honestly, I dont even know what else to do.
Please dont send me to the old forum post where you have this 6 steps to do about overheating, background stuff, driver updates and all that couse Ive seen it 2894040023 times yet, it DOES NOT SOLVE ANYTHING.
So far only reinstall has solved a few times, but im getting tired of doing that honestly, what is the problem ?? has anyone else beeing having this issue ? any solutions??

Some of the suggestions in the mega thread about this issue have helped a few of the players.

some suggestions you can try:

  1. disable integrated GPU on you cpu in BIOS settings, using only your RTX 2070.
  2. disable full screen optimization in windows 10 for overwatch program.