XPS 8700 PSU Fan

Contact Dell Tech Support ASAP, either by phone, chat or email. Have your Service Tag handy.

They'll decide if they want to send you the PSU or send a tech with a PSU to fix it.

In the US, you have 21 days from invoice date (not delivery date) to request a replacement system, if you'd prefer to get a replacement rather than have this one fixed. Keep in mind that a replacement may be a refurbished unit per Dell's warranty, but will come with the balance of the warranty from your original system.

Thanks Ron.  I just contacted Dell tech support.  They had me update the bios from A08 to A10 to see if it would resolve the issue.  I'll see what happens tomorrow morning when I start the computer.  Oddly, the PSU fan not spinning / noise issue happens when the computer has been off for several hours.  The fan spins right up if only a quick restart is performed.  The Dell tech is going to call me tomorrow afternoon.  He did mention about sending me a new computer if the problem persists.  (I think he said new computer, not new PSU).  I appreciate you telling me about the refurbished units and I'll ask if it will be new or refurbished if it comes to that.

I don't see how updating BIOS is going to fix a PSU fan problem like you described. And there's always a (small) chance a flash update will brick the motherboard.

I'd be cautious about doing the BIOS update. Be sure to read./follow the instructions and disable your anti-malware software first.

And when the problem persists, ask either for them to replace the PSU or get you another system, and certainly ask if it will be new or refurbished. I bet it's the latter.

Post back and let us know what happens...

One of my 8700s has a coil whine on the WiFi card. Disable wireless and see if the noise disappears. It took a while to identify, and I've since switched everything to wired ethernet.

I did update the BIOS from version A08 to A10.  (I read you reply after I did it or I may not have even tried) As you said, it didn't fix the problem.  As I'm typing this the PSU fan is not spinning and there is a high pitched whine from the PSU.  When I touch the fan blades the pitch/frequency of the tone changes, but does not subside.  After giving the fan some help spinning, it spun up and the noise subsided.

Anyway, Dell just called and they are sending me a new PSU.  If the problem still persists after I install the new PSU, the tech said they would send me a new system.  I questioned the tech as you suggested regarding a new system vs refurbished.  He said that it would be a new system since it is within the 21 days.  He also offered to send a new system right now if I chose.  I figured I would give the new PSU a try first.

I was reading that some of the aftermarket PSU's will vary the fan speed or it may not spin at all depending on the temperature & load.   I asked the tech if the stock Dell PSU fan functioned this way and he said it doesn't and that the fan should always be spinning when the system is on. 

Thank you again for your help & suggestions.  I'll post again once I install the new PSU.

UPDATE

It took two weeks (backorder), but I did receive the new PSU.  No problems with the swap.  It's quieter than the original and the fan works as it should.  The replacement is from a different manufacturer.  Some minor differences in the case and the internals look a bit different by peeking in the vent holes.  Although I wish I didn't have to go through the whole process, Dell did stand by their product.  Here's the info in case anyone has a similar issue:

Original noisy PSU:

SHENZHEN HUNTKEY ELECTRIC Co, model HU460AM-00

Replacement quieter PSU:

DELTA ELECTRONICS POWER Co, model D460AM-02