Basically you don't need to use the factory fans at all. In my opinion the reason why they fail so fast is not because of mining but because those fans are generally designed to be mounted horizontally in a PC case. When they are mounted vertically like in an open air rig their life span is reduced.
Back in 2015 I bought tons of GPUs for almost free because they were mined with and the fans were dead. The GPU worked perfectly but the fans either ran slow or rattled. I took off the fan shroud and put some case fans and they ran cooler than stock. Only issue was that you need custom wiring for the 12V fans and they are bulked between the GPUs because case fans are fatter than regular fans.
My first farms consisted of 2 video cards.
There were no long raisers back then, and my video cards were installed horizontally in the motherboard, like other video cards. I used these computers for mining, work, watching movies, playing games.
After 2 years and 9 months, I saw that the fans fell off.
I put the fans back in place and took the video cards to the seller.
My money was returned to me, because the examination recognized the marriage of the cooling system.
If I bought an inexpensive video card without a warranty, I would just replace the broken fans with inexpensive case fans. But if I buy a video card with a 3-year warranty, I will require the seller to repair the defective cooling system for free. Of course, if the profit of the video card is equal to $ 2 or higher, then I will not contact the seller to wait 45 days and lose 90 dollars. I'll probably fix the problem myself.
