Ugly Phrase on First Bootup: ‘CPU Fan Failure’

The new PC I’ve been salivating about arrived yesterday — yes! on a Saturday! I did all the necessary last-minute backups and so on, exported various programs bookmarks/favorites and settings, and even burned a new installation CD for the correct version of Ubuntu (Linux), since I can’t use quite the same version that I’ve gotten used to for the last few years. All I had to do was set up the new PC, hook up the backup drive, and go.

Except…

On the very first startup of the new PC, before it even booted into Windows (which it came installed with, although I don’t expect to use it much), a message appeared at the top of the screen:

CPU fan failure.
Strike the F1 key to continue or F2 to run the set-up utility.

Hoo boy.

I knew what the message “meant,” sort of. Recent PC models come with two internal fans: one to cool the overall chassis interior (for all the heat generated from the spinning drives and some of the electronics), and one to cool the CPU itself — the single most important chip in the computer, the brain, the central (in all senses of the word) processing unit.

Imagine a toaster, plugged into the wall. You push down on the lever and walk away. If you’re lucky, you remember to check on your toast within a minute or two. If you’re not so lucky, you find out the hard way that this particular toaster’s timer isn’t working, at all…

I still have the old PC up and running, so I could get online and look around some. It turns out to be a fairly widely reported problem — not common, but not unheard of, either — for desktop computers built by this manufacturer. Two solutions seem to be recommended:

First possibility: Update the computer’s core software, the BIOS, to an updated version. (The BIOS kicks in before what you think of as the computer’s operating system itself. When you turn on the power switch, what’s really being turned on — even before the hard drive starts to spin — is the BIOS. The BIOS then instructs the drive to spin, and so on.) This process is called “flashing the BIOS,” although it’s not as exciting as the phrase makes it sound. I’ve done it before. True, there’s always (for me) a little frisson of danger: if you hose the BIOS, you may or may not have a looooong road to recovery. But it’s not difficult. Still, this didn’t seem the likely solution: the latest version of the BIOS for this model was released in June, and the computer itself was built just a few days ago.

For the record, the reason the BIOS is important in the case of this error message — at least for this model, possibly for the manufacturer’s desktops in general — is that it runs several tests to be sure the computer is ready to start working. Some of these diagnostics are fairly mundane (e.g., is there a keyboard attached?), and some are more important to the machine’s health and safety… like the diagnostics which confirm that both fans are spinning. A known bug in earlier versions of the BIOS apparently didn’t run or interpret the CPU fan diagnostic test correctly — and reported the fan as not working even though it was.

Second possibility: Sometimes a cable inside the computer chassis just slips down and physically blocks the fan, preventing it from turning. (The highly technical solution: move the cable out of the way.) Again, this seemed unlikely to me: I’ve almost never bought anything but Dell computers, and it sounded too weirdly slapdash to me. The interior components of these computers fit, and just aren’t that crowded that a cord might get pushed down in amongst the blades of a CPU fan…

Surprise, surprise. I removed the cover and found the culprit (click for a larger view):

Here, I’m holding a black-and-yellow cluster of cables at one end of which there’s a black plug — circled above — while the other end comes from the computer’s power supply. The CPU fan itself should be pretty obvious. The photo (taken after I’d plucked the culprit from its lair) makes it seem that the plug is actually resting on the fan, but that’s deceptive: the distance from plug to fan was actually about four inches at the time I clicked the shutter.

In any case, I moved the plug out of the way — tucked it behind a couple of sheet-metal braces — so it won’t fall back down. And that seems to have solved the problem.

No, I have no idea what the purpose of the yellow-and-black cables + plug might be. I couldn’t find anything it should have been plugged into, so assume it’s there for some possible future expansion. It doesn’t seem to be hurting anything. It’s just like a vestigial tail. Literally a loose end. And yes, kinda slapdash.

But if anyone reading this works for Dell Computers — especially those manufactured at the Foxconn plant in Mexico, across the border from El Paso — please ask your workers to clip the damned thing out of the way, eh?

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(2013-07-29 ~11:00 a.m. edit to add) For anyone who might want to know the machine’s specs, in case they’re having similar issues:

• Model: Dell XPS 8700
• CPU: 4th Generation Intel Core i7-4770 processor (8M Cache, up to 3.9 GHz)
• RAM: 16GB (partitioned as described below, under “Operating systems”)
• Hard drive: 2TB
• Video: NVIDIA GeForce GTX 645 1.0GB GDDR5
• Operating systems: dual-boot, as follows:
  • Pre-loaded: Windows 7 Home Premium (installed in first partition, ~1TB)
  • Following setup: Ubuntu Linux 12.04 LTS (installed in second partition, ~1TB) (default boot OS)