vega 64 fan swap problems

[Pesky Ngon]

so I have 3 vega 64s for 3D rendering work. due to thermal throttling caused by having them stacked together I decided to strap a more powerful delta fan onto the coolers. (PFR0912XHE)

Its a 4 wire fan. due to its power I cant use the 64s fan header, or even a mobo header for the power wires. so I have the red and black wired up to a molex 12v. and then the blue and yellow wires onto the 64s fan header to control the speed. but when I turn the pc on the fan spins at 100% as if the blue and yellow are detached. and Radeon software shows 0rpm on the fan as if it isn't connected. anyone have tips for fixing this?

[Spaceman_Wil]

Hm. Is noise the concern with it running at 100%?

[Pesky Ngon]

4 minutes ago, Spaceman_Wil said:

Hm. Is noise the concern with it running at 100%?

yep. each one is 75db and eventually I may have 4 of them. that's fine, but only when im rendering. when im doing other work I need it to be much more reasonable or I cant concentrate. 

edit: hell, even if I was fine with it, I imagine id get a noise complaint from the neighbours  

[Spaceman_Wil]

Maybe it's the open pins on the 64s that are causing it to show 0rpm. It could be it can't detect the fans otherwise? Not sure of a solution if that's the case.

 

I have a Noctua NF-B9 strapped to my GPU and have it plugged into my mobo in just a system fan slot. For my purposes it is both super quiet and keeps my 2080 working great. Keep in mind I have the NZXT Kraken G12 strapped on it too with an AIO. I can't hear the fan and my temps never pass 55C under full loads. I can control the fan speed just through the mobo software but unfortunately I've not got it linked to the GPU temps yet. Hasn't been a problem yet tho Might be an alternate route for you?

[Pesky Ngon]

Just now, Spaceman_Wil said:

Maybe it's the open pins on the 64s that are causing it to show 0rpm. It could be it can't detect the fans otherwise? Not sure of a solution if that's the case.

 

I have a Noctua NF-B9 strapped to my GPU and have it plugged into my mobo in just a system fan slot. For my purposes it is both super quiet and keeps my 2080 working great. Keep in mind I have the NZXT Kraken G12 strapped on it too with an AIO. I can't hear the fan and my temps never pass 55C under full loads. I can control the fan speed just through the mobo software but unfortunately I've not got it linked to the GPU temps yet. Hasn't been a problem yet tho Might be an alternate route for you?

I was thinking the same as you with the two empty pins being the problem. im currently in the process of soldering the old fan onto the red and black only. then just tape it so it cant spin. not elegant, but all I want is the performance so eh. I considered doing the mobo pins, but im afraid id have the same problem cos a mobo header cant supply anywhere near enough power for this fan. so the power wires would still be on molex.

[Pesky Ngon]

1 hour ago, Pesky Ngon said:

I was thinking the same as you with the two empty pins being the problem. im currently in the process of soldering the old fan onto the red and black only. then just tape it so it cant spin. not elegant, but all I want is the performance so eh. I considered doing the mobo pins, but im afraid id have the same problem cos a mobo header cant supply anywhere near enough power for this fan. so the power wires would still be on molex.

well. that didn't do shit. 

[Spaceman_Wil]

1 hour ago, Pesky Ngon said:

well. that didn't do shit. 

Though it doesn't supply enough power, does the card detect the fan when the fan is hooked in?

[Pesky Ngon]

Just now, Spaceman_Wil said:

Though it doesn't supply enough power, does the card detect the fan when the fan is hooked in?

I cant test it because it would blow up the header from what ive been told. 

[Spaceman_Wil]

Just now, Pesky Ngon said:

I cant test it because it would blow up the header from what ive been told. 

Ah gotcha. I hate to say it, but you may just need a quieter fan.

[Pesky Ngon]

1 minute ago, Spaceman_Wil said:

Ah gotcha. I hate to say it, but you may just need a quieter fan.

ahahaaha. nah I don't give up that easy. ill figure something out. am looking into other ways to generate a PWM signal.

[Pesky Ngon]

On 1/13/2020 at 9:26 PM, Spaceman_Wil said:

Ah gotcha. I hate to say it, but you may just need a quieter fan.

its been a stupid long time, but thought youd be interested to know I was able to get it working by having all the old fans wires attached and then attaching just the pwm wire from the new fan. only slight problem is I need to invert the signal because PC fans read it an odd way but hey, at least it works.