So I did a lot of tests yesterday, and this morning. At first I was finding the PC chuggy, but then properly updating AMD and Nvidia drivers swiftly solved the problem.
I did also an extended SMART test t make sure the SSD was all right, which it is.
I stress tested with FurMark and Prime 95.
While stress testing, and gaming, I noticed the Gamecube would get so heat soaked. So I decided to put back one of the fan as an exhaust, and I did a small funnel to redirect the intake fan’s air toward the converter and the CPU fan. And that helped a lot. The CPU when gaming do sometime spike at 99C, but it doesn’t affect performance much.
Here’s a test of all the noises of the Gamecube, when starting, under beginning stress test, and when closing
I did so many recording for either them for not work, or me forgetting to save them, so sorry for how lackluster they are. I was able to fully screen record with the Gamecube emulation, but when trying CS 2 and GTA V, I would get after about 5-7 minutes frame dropped because it was too taxing on the GPU. So i recorder the Game with the Windows built-in game recorder.
Gamecube emulation, 1440p, no anti-alliasing, no FSSA (Wind Waker constant 30 FPS, Mario Kart constant 60 FPS)
CS 2, 1440p, high settings, average 60 FPS
(Old) GTA V, 1080p, high settings, average 50 FPS
(I just noticed GTA V refresh rate was setted at 50 Hertz, that explain why that time it was at 50 when a previous time I was able to get 60 
, will add a new recording soon)
(New) GTA V, 1080p, high settings, capped 60 FPS
So I will do the glamour shot and put it for sale later today. Do you think that $740 US is reasonable as a price to sell it?