Fan replacement amiga 2000

[Elahrairah]

Hi guys and girls

So I did a fan replacement on my old Amiga 2000, noctua fan, the one recommended, 12v Noctua NF-A8 ULN. I did the wiring and when I test it the fan spins, low noise, perfect.
But when I connect the motherboard to the power supply the Amiga boots for a few seconds and then stops. No picture, nothing. All cards (I don't haved any) and floppy are removed.
Tried the old fan and everything works again. Amiga boots and works fine.
What am I doing wrong?
Also maybe good to mention the metasl psu cover has small (ventilation?) holes. It's not like the Amiga 2000 psu I've seen online. Maybe this type of psu doesn't support it?

edit: I just realized that this post probably should be in the Mod section. Sorry guys! I will move it to the mods section. Moderators you can remove this post.

[Malakie]

Just noticed your post being I had the same exact problem. Some A2000 power supplies (cannot remember make or model name) monitor the fan draw power level. I replaced my fan with the same identical fan you did, and poof.. same result.. powers on then just shuts down. Replacing the old fan makes it work again.

I came here hoping someone might have a solution for the A2000 power supply to fool it into thinking the fan is pulling enough power so it does not shut down.

If anyone else reads this and happens to know, it would be a great bit of information for everyone.

While I have worked extensively on Amiga boards and parts, I never really dug into the power supplies themselves. Until now. If someone has the schematics or knows how we might be able to fool the power supply into thinking the new fan is drawing enough power to be on, would be a great help!

For now, I will go back to the old, noisy vibrating fan.. which is a bummer since I will then have to pull this thing apart again.