XPS 8950, Noctua NH-U9S FAN FAILURE

More than likely, the Noctua fan runs too slow. You can either use a splitter cable and use the Noctua fan along with the stock fan or just use the stock fan if it is the same size. Any fan that has the same RPM ranges as the stock fan should stop the BIOS errors.

There is more to the riddle of the diagnostic startup error the simply rpm.

If your pancake fan is 92mm you can add it to the back of the Noctua cooler with a PWM Y-splitter adapter cable. Make sure the Dell OEM fan is connected to the 4-pin side of the PWM Y-splitter.

something like this . . . does not have to be Noctua, but must be a PWM connector

@moxxy 

Apparently, I am just catching up with you on this issue here on this forum.  But, I may be a bit further down the road from you, so be sure to read this entire thread.

In that thread I note that I really wanted to go with one of the best, most loved coolers on the market: Noctua, BeQuiet, et. al.  But, not one of them has a good rep for working with the BIOS and not throwing that error.  After noodling this a bit, I went with the OEM vertical cooler described in that thread - pros and cons are provided there.

Besides OEM fans/coolers, the Corsair ML120 Pro is the *only* fan that I can find that had reliable/repeatable behavior in a Dell and the only other cooler is the Vetroo V5.

I have a Corsair ML120 fan being shipped now, and I intend to experiment a bit using it as a case fan, and since it's the same size as the stock fan in the OEM vertical cooler, I may swap that out too, just as a trial.  My goal is to lower fan noise at idle, and to not throw any errors.  If the Corsair also provides better cooling, that would be a plus.

Hope this helps!

@moxxy 

Here's where I wrote about the OEM premium cooler, if you are interested.

I totally agree with you on that one.  Only if I can even adjust the fan speed lower limit which I think is the cause of the BIOS error but no such option in the BIOS, updating the BIOS to the latest one for XPS 8950 did not help (I updated it back to the old version) . The other major proprietary problem is the power supply ,  Upgradability in Dell is a myth, only if one can find the parts that works and fit the system.

There is certainly a lot of Dell proprietary nonsense . . . but this particular upgrade you could have brought to fruition.

i was thinking about swapping out the Noctua fan , after all, it is only the BIOS error message that annoys me , the Noctua coller works when it is in Windows , lowers the temperature substantially , no system or application crashes.  Do you have the dimensions for the Corsair ML120 Pro fan and you are not sure that the Corsair fan will not cause any Bios error ?

Corsair ML120 Pro is a 120mm fan . . . you need 92mm fans for your Noctua cooler. Are you able to add the OEM pancake fan to the back side of the Noctua cooler with a PWM Y-splitter adapter cable . . . or is there something blocking that install?

To be fair, I don't see where Dell says you can upgrade anything you want. The only place where Dell mentions upgrades is when discussing accessibility in the chassis and only mentions upgrades to the CPU, GPU, memory, and storage. As for Dell's proprietary designs, I would think the proprietary nature of their design costs them more than they benefit. 

Adding a fan should be a simple procedure and it is my fault that I assumed that from my last Dell system to which I installed a "vertical" CPU cooler with no error. Talking about storage , I added a harddrive but I have to get the blue plastic caddy to accomodate it , I wish Dell had included a piece of plastic considering the cost of the system.  I agree with you that Dell proprietary design costs them more than they benefit, they could have attracted more customers. In my youth, I used to assemble my own system but as one gets older , life curbs one's enthusiasm, don't have that energy to do that any more and now I am paying the price for my "laziness" .