XPS 8900 Fans

I replaced the rear case fan with a Noctua NF-B9 PWM Cooling Fan. They run about $14 on amazon.

PSU fans are noisy. I have upgraded the PSU in both of our 8700s and the OEM noisemaker is in a box in the garage.

CPU fan isn't that bad except as you commented, during startup.

Thanks for the Info Dan. I believe that PWM version fan comes with a 4 pin adapter and the rear case fan in the XPS 8900 uses a 3 pin. How did you make that work? Does it run at a fixed speed?

I'm not a fan expert so if someone wishes to correct me please do.

My understanding is that fan can be PWM or Voltage regulated. When connected to a three pin connector the speed will be voltage regulated. I just plugged it in and it works, and it is quiet.

I have also upgraded power supplies. Stock power supply has a noisy fan.  I went with a Seasonic X-650 and it is essentially silent. The PSU has a switch to run with or without the fan at idle and I cannot hear the difference when the fan is running or if it is stopped. 

And, the upgraded graphics card fans are also really quiet. Much quieter than the stock GT 635. I've had GTX 760, GTX 770 and GTX 970s in and the 970 makes the least noise. GTX 770 made the most but still quieter than the GTX 635.

I haven't felt the need to replace the CPU fan. It spins up fairly loud at startup, but it idles down fairly quickly.

I have been experiencing EXACTLY the issue you describe.  I took delivery of this XPS 8900 less than 2 months ago.  The sound I heard was exactly as you described--it sounds like a hard drive being accessed, for long periods of time at a stretch.  The only problem--like you, I have an SSD.

I finally "got under the hood" and tracked the sound to the power supply fan.

My experience with Dell and spare parts has never been good--it is with trepidation that I will inquire about a replacement under warranty.

I contacted support and they said they would send a new power supply. When I received it the power supply was marked as refurb. I could see dust and junk on the fan blades. I just sent it back and kept my original. There is no way I was going to allow dust and junk from someone else's home being introduced in to my air system in my home. This just seems wrong on so many levels that they could send me that power supply.

So now I still have the original noisy power supply in my system. Which is only a few months old and was defective upon delivery. I did not contact them again because each time doing so is a lot of time out of my busy schedule. I have to say, I am not the huge Dell fan/cheerleader that I had been for the last 15 years. If they had told me up front that they were going to send me a refurb power supply for my brand new system, I could have saved them money on the postage both ways.

anyone know the specs on the stock fan?  Power ratine, RPM, airflow, dbs?

If you are referring to the fan in the power supply, the one in my power supply is a Yate Loon D90SH-12. Specs are here

 to be clear, I did not proceed modifying the PSU fan. I didn't think the PSU was worth investing one or two  hours of my time and a $10 fan.Maybe some day when I have absolutely nothing to do.

I considered replacing the stock PSU fan. I'm using the stock 8700 PSU in a small custom build and the fan noise of the PSU was bothersome. If I had more time I would have experimented.

It appears possible to fit a 120mm fan on the PSU. New mounting holes would need to be drilled along with drilling more ventilation holes in the PSU case.  I mounted the fan shown with one screw and it will clear the electronics inside the PSU.

Here are a couple of pics.

I also just bought a new XPS 8900 i7, however I do not have issues with any of the stock fans yet. Now, related to the same topic of 8900 fans, have anybody "already" added a Front fan as an intake? What brand and size is it recommended? Low noise type is desirable of course. Also, did the holes in the front grill lined up? Thank you for your time folks! Andrew

Assuming the mount is the same you can fit a 92mm fan on the front on the inside of the case.

(edit: assuming the 8900 case is the same as the 8700 case, which I think it is ...) 

airflow is meh, because the case isn't opened up.

you can cut the opening and fit a 120mm or a 140mm.

I am currently having an issue where my Dell XPS 8900 keeps giving me an audible 2-beeps every minute or sometimes almost 30 sec after my computer is on for awhile... everything I have read has stated this can be caused due to overheating... and as I have upgraded my graphics to the NVIDIA GeForce GTX 970 and also my PSU with the Corsair CX750M, I can see this as being possibly... If I wanted to get more cooling power on my CPU by upgrading... what do I need to look at getting? I havent messed with building computers for over 10+yrs until the last couple of months... so I know Im way outdated hahaha Please help!

Hi Dan-H and thank you for your quick and assertive response, I appreciate it. To test the fitting of a 92mm, I took the stock case fan at the back and position it in the front of the case, which did not work as the holes do not line up and also, the grill holes are bigger than the standard fan securing screws. To install a 120mm or bigger is not possible in the configuration I have as the Hard-Drive cage is in the way. It looks like it is easier just to leave it as is or play with another 92mm fan but with higher air flow capacity for the back of the case. My 8900 does not have a temperature issue yet but wanted to see what the Fan options are for the front of the case. Thank you again, Andrew  

The fan I installed was the OEM Fan from an xps 8700 after I upgraded one to a Noctua. It is 92mm. 

I'll take some pics on Sunday as I'll be working on that system.

I may cut the front bezel to install a 120 or 140mm fan. as there isn't very good openings.

Please note that I removed the HDD cage. This system has one HDD in the HDD2 position, and an SSD in the second optical bay.