ArticlesI just discovered the source of an intermittent boot problem I have noticed with my new computer. I haven’t Googled it yet, or tried to work out how to fix it. However, it was so bizarre, I wanted to tell someone immediately, and I know at least some of you guys will understand.
The symptom was that the BIOS intermittently freezes up just before the RAM test. Today, I discovered how to reliably reproduce (and how to avoid) the problem.
All I need to do to reproduce the problem is to leave an iPod Nano in its USB base during boot-up. All you need to do to work around the problem is to remove the iPod Nano from its base.
In fact, if I remove the iPod from the base while the BIOS is frozen, the BIOS will immediately unfreeze.
I have two iPod Nanos. They each cause the problem.
It isn’t a power-supply overload issue, because I had all of my hard-drives unplugged while I tried to narrow down the cause. I also tried leaving an iPod charging, while unplugging my Samsung D600, but it had no effect.
I assume it is some fancy “Use the USB-stick as a drive/cache” feature of the BIOS which is going very, very wrong, but as I said, I haven’t Googled it yet.
If I didn’t see for myself how tightly correlated the iPod and the BIOS freeze were, I never would have believed it could possibly be related!
Weird.
Comment by Iain on March 11, 2009
Does your bios have an option to boot from USB? It could be that it’s busy poking the ipod trying to decide if it’s a bootable device or not.
Comment by Iain on March 11, 2009
I’m in critic mode now: your issue, while bizarre, doesn’t compare favourably to the 500 mile email story (at http://www.ibiblio.org/harris/500milemail.html). Maybe the cause and the fix will add to your problem’s bizarreness?
Comment by configurator on March 11, 2009
Iain, when youboot from USB, 512 bytes are loaded from the USB drive, then the boot happens if the first 2 of these bytes have a certain magic number. No reason to hang there, except if the magic number was there and the boot hung. In that case, it wouldn’t resume when the iPod was removed.
Comment by Julian on March 11, 2009
Iain,
That’s not fair. The 500-mile email story is a classic legend that parents tell their kids when they don’t want them to grow up and use sendmail. It rates with classics like the missile-firing kangaroos.
You can’t dismiss the bizarreness of my bug report just because it doesn’t rate with that.
The problem isn’t about booting from USB, because this occurs well before the OS is loaded. It hasn’t even tested memory yet.
A quick Google revealed someone else being told it was related to IRQ conflicts. They didn’t get given any solution that was less painful than simply removing the iPod at start-up, and plugging it in once the plug-and-play system was loaded. At that point it was bed-time, so I didn’t research any further.