D901C will not boot with iPod plugged in

I have a D901C [if it matters, the MB revision is 5.0a by the sticker inside]. I have the ultra-strange problem -- if I boot my laptop with my iPod plugged in, it WILL NOT boot. Either is just crashes or reboots.

I have a 80 GB iPod [5.5G I believe] which has the newest firmware, etc. but I bought it quite a while ago.

I have these USB items plugged into my laptop [through hubs, etc.]:
1) XBOX 360 HD DVD drive [I forgot to buy a dvd drive for my laptop.. duh]
2) External USB Hard Drive [maxtor or some such]
3) 4 GB Memory Stick

These are the only items which come up during boot so they are the only ones I listed. When ONLY these items are plugged in, everything is fine.

If I plug my iPod in [it can be the ONLY thing plugged in] it results in either a crash or a reboot when it enumerates the USB devices. I've never seen this happen on any of the other laptops I own, just this one. Does anybody ELSE have this problem on theirs or am I just freakin lucky??

 

Well, first the bad news (or good, as you will ) is, you're not alone; a quick google pulls up a number of references to similar-sounding problems.

This post seems to indicate that the problem arises from the iPod attempting to pull too much power from the USB port, and that the problem might be caused/aggravated by a weakened battery in the iPod.

It could also be a problem with the laptop's power supply, as suggested in this posting. Does this issue happen only when you're running on battery, or also when you're plugged into AC. As a follow-up to that, if it happens when you're on AC, do you regularly keep the battery in the computer even though you're running AC? If I recall correctly, if you keep the AC plugged in all the time, the battery may be chronically overcharged, which will eventually wear out the battery.

 

I have a 30GB video iPod (5th generation i believe). I used to have the same problem in my old Dell Inspiron 8600. The computer wouldn't even boot past the bios boot screen. The progress bar would reach about 90% and then just stop. I'd have to disconnect the ipod and reboot the computer for it to work.

However, in my D901C, I can boot it up with the same iPod connected, without any problems.

 

I've had some random USB devices stop my desktop from booting up completely and sometimes they'll make Vista hang at the loading screen.

I have no idea why

 

My Sager will not boot with an external hard drive plugged in, but it has no problems booting with my iPod touch. My iPod is flash-based and I don't think it is being detected as a hard drive, which is why it boots. Your iPods, on the other hands, are probably being detected as hard drives. That is the only thing I can think of.

 

There is a very simple reason for the laptop not booting and a very easy fix. Your laptop recognizes the iPod and wants nothing to do with it, so it will not start. Do the world a favor and destroy the iPod while you have a chance.

 

Actually, after doing a little poking around on google, the problem seems to be related to power issues. The linux folks seem to have done a little more digging on these issues, as indicated by these two posts: one and two.

Also, it seems to have something to do with whether or not the USB device in question is a so-called "composite" device (a USB device with multiple interfaces) and whether or not the device is a high-speed device or not. A non-high-speed device cannot draw more than 100mA, and a high-speed device cannot draw more than 500mA.

Finally, it may also depend on whether or not the USB port the device is plugged into is closely connected to the motherboard or extended - in this case, the off-board ports tend to have less signal fidelity.

The other piece of the puzzle comes from the implementation of the PnP protocol for USB, under which, if a lower-numbered USB device is disconnected, all higher-numbered USB devices are shifted down; if the device is then reconnected, it takes a new high number.

Basically, what seems to be the crux of the problem (as near as I can guess from interpolating among the various hints) is that, for whatever reason, either loss of signal fidelity that causes the device to not accept an assigned address, or a power draw that spikes over the cut-off threshhold, causing the device to be disconnected, the BIOS is probably enumerating the USB devices that are connected when the power button is pushed (which the BIOS must now do in order to support boot-from-USB as well as USB keyboards and mice), passing the enumeration to the OS, but not picking up a device disconnect caused by loss of signal fidelity or cut-off due to a power surge, which, if it happened to a low-numbered device (i.e., one that was enumerated first, such as a bootable usb drive), could cause all higher-numbered usb devices to drop in ranking, thereby rendering the enumeration table passed by the BIOS unusable. The resulting confusion would most likely cause the OS to lock or hang during boot-up.

In particular, I think that Chaz' statement about his flash-based iPod probably indicates that something sort of like this is happening. The rationale would be as follows:
1) On start-up, the BIOS begins enumerating boot devices, including USB boot devices, and then enumerates any other usb devices.

2) Because the iPods (other than Chaz') are identified as hard drives, they get enumerated early, meaning that they have a low number.

3) The BIOS finishes enumerating all the other usb devices, assigning them high numbers. The BIOS then passes an enumeration table (my own invention, I don't really know how the BIOS passes USB data off to the OS, but my guess is it's some sort of data table built up during initial enumeration).

4) After enumeration, but before the OS takes over, the iPod causes a power spike on the USB port as it starts itself up - the power load generated by a device (other than a flash device) is going to be the highest at a cold start, when all of the different mechanisms must be energized, and motors undergo the greatest strain overcoming the inertia of physical systems as it spins up the physical disk. This power surge causes the system (probably the host controller) to drop the usb device as a self-protection mechanism.

5) When the system goes to look for the proper boot device, it will see a USB device in the BIOS-generated enumeration table that needs to be checked, but when sends a signal to that device using the address provided in the BIOS-generated enumeration table, it either gets no response, or worse yet, because any higher-numbered usb device would now be occupying that address, gets a completely incomprehensible answer back. As a result, the system would probably simply hang.

I think that, if true, Chaz' statement helps to support my wild suppositions because, if its true that his flash iPod is not being enumerated as a boot device, it would be enumerated at a higher number than any bootable usb device, and any subsequent troubles (signal or power surge) that caused his iPod to be disconnected would not effect the boot devices listed in the BIOS-built enumeration table. Thus, even if his iPod disconnected and corrupted the BIOS-built enumeration table, the system could still safely boot through to completion, at which point the enumeration table would be updated under the OS' normal PnP procedures, and the corruption caused by the disconnect would be fixed.

Also, since Chaz' iPod is flash-based, it probably imposes a smaller power load on the usb port at startup, meaning that it is less likely that his iPod would exceed the 100mA or 500mA power limit, and therefore less likely that the host controller (my guess, again) would disconnect his iPod and corrupt the BIOS-built enumeration table.

What does that all mean, and how can you avoid the problem? I would suggest either (a) don't leave the iPod plugged in when you boot up the computer, (b) get a usb connection for the iPod that is self-powered and not solely powered off of the USB bus, in order to reduce the power load strain the iPod puts on the system at startup, thereby minimizing the chances of having a self-protective disconnect due to a power spike that exceeds the power limit, and (c) make sure you're using high quality cables, that are no longer than necessary (in order to improve signal fidelity) and make sure that your USB connections are tight so that there isn't any slippage (a loose connection could cause both a loss of signal and a power surge as current sparks across the loose connection.

Now, as I hope I've made abundantly clear, this is all my speculation based on very rudimentary research I just did now in about an hour or so on google, so I could be totally and completely wrong. I would suggest that it might be fruitful to follow up on the linux-related links above, because they seem to have much better experience of potential usb-related boot problems.

EDIT: Yeah, yeah, I know, another novel - whaddya expect, I'm a in love with my own voice.

 

Shyster1, you`re driving us nuts, but you put a helluva`n explanation

 

I know, I know, it's just that, well, I miss


Thanks! I read through it again and I'm a little shocked at how disjoint it is in places, so I'm not surprised if it was hard sledding for y'all.

I think it can probably be boiled down to something like the following: the iPod is either drawing too much current through the USB bus at startup (when both the computer and the iPod are starting up at the same time), or else the connection between the iPod and the USB port is loose or weak, causing the iPod to not answer the computer's queries properly.

In either event, what probably happens is that the iPod initially gets enumerated by the BIOS, but then gets disconnected, so that the enumeration table passed to the OS by the BIOS is corrupt, and causing the bootloader to try looking for a potential boot device (i.e., an iPod that gets enumerated like a hard drive instead of as a flash memory device) that is no longer where it should be according to the enumeration table. As a result, the bootloader probably hangs.

Any better?

 

No. But I still like the novel thing

 

That's actually a pretty good picture of ole Wilson, isn't it?

 

The weird thing is that the problem actually happens when it is plugged into a powered USB power [so I kind of assume that rules out the power issues]. Another piece of the weirdness is that the behavior actually changed after updating to the newest software on the iPod.

The prior version, it would just hit the USB enumeration section and, when it hit the iPod, it would reboot. NOW, after the update, when it hits the iPod, the laptop totally locks up. Seriously bad -- corrupts the display, everything.

My personal theory is that Apple, being Apple, implemented the USB on the iPod in a SLIGHTLY non-standard way and the BIOS implementation of reading the USB can't cope with their badly implemented USB.

Yes, I know, why do I HAVE the iPod in the first place.... well... 80GB worth of small storage I just couldn't help myself. If Microsoft would just get with the program and make a bigger version of the Zune, I'd be ALL over it.

 

That's another distinct possibility (after all, I have an old Compaq laptop that gives linux fits because the ACPI implementation is bunged up, which is ironic considering that Compaq was one of the founders of the ACPI standard).

I think the question is not why you have an iPod, but why you leave it plugged in when you boot your system. Unplugging it for boot seems to be the simplest solution.

 

He explained that a 80 GB external drive is something worth it.

I would check the boot order from BIOS and leave any USB or such drives at the bottom of the list.
If that doesn`t work , Shyster1`s advice is simple but brilliant

 

My desktop doesn't boot up with the iPod plugged in either. Must be a universal issue.

 

Should come with a warning then

 

Ooops! I guess my glasses ... wait, where'd they go ... oh, on top of my head again. Who keeps putting them there?

A tiny little external with 80GB is certainly nothing to sneeze at (I have a big clunky LaCie 250GB - it's nice, but clearly doesn't "go" with the laptop). Still, unless you're booting from an external (in which case you've obviously solved the USB problem ), I would think that best practice would be to unplug it for boot-up; the BIOS code is rinky-dink enough as is, and I don't see the sense in asking it to do more than it really needs to do to get the computer running (I have no direct evidence for this; however, I did read through part of a readme Phoenix issued with its BIOS editor listing the different revision changes, and, aside from the massive quantity of typos and etc, I just had to laugh when I found one revision item identified as "changes to correct speling errors" - for me that raises considerable doubts about trusting the BIOS to handle anything even faintly exotic).

 

I was cogitating a bit more on the no-boot-with-iPod-plugged-in problem, and I was wondering if you could check some things on your system.

First, go into BIOS setup to see if boot-from-USB is enabled. Second, with the system running and the iPod plugged in, go into the administrative tool called disk management and see how the disk management utility reports the iPod, in particular, does it report the iPod as an active partition?

One of my cogitations was that, if boot from USB is enabled in BIOS, the system might actually be trying to boot from your iPod (particularly if, for some reason, the iPod is marked as an active partition) and, assuming contrary to my earlier speculations that the iPod might be getting disconnected (I'm changing this speculation in part because you said that you have your iPod plugged into a separate power source, so it's not drawing all of its power through the USB bus), your system might be hanging because it expects to find a boot sector on your iPod and in fact cannot (mainly because, I'm assuming, you haven't turned the iPod into a bootable device).

I had a problem that seems somewhat similar to yours with a hdd on which I had damaged the WinME OS and boot sectors (and then tried to reset the boot sector by copying same from another WinME installation on a different system); namely, the system would go through POST, find the (supposedly) bootable hdd, and then hang because it couldn't get a good boot from it.

 

I just fixed a Dell Inspiron laptop with a similar boot hang problem. The machine would hang if the iPod was plugged in the USB port, or even a powered USB hub. The machine is 5 years old and is USB 1.1
The machine would hang in the boot sequence right before it would go to Windows start part. I took USB completely out of the boot sequence and that didn't do it. What did do it, based on a suggested fix from a Dell guy.
With the iPod unplugged, here is the Dell suggestion which might help some but not this Dell (keep reading below for the fix that worked):
1. Restart the System. (Unplug the IPod from the system)
2. Tap <F2> at the Dell Logo to access the BIOS.
3. Go to the Advanced Tab, and disable the USB legacy support.
4. Save the changes and exit.
But on the 1100 that I was working on, it had a older bios and used the Alt-P procedure to page through BIOS options. On page 3, there was a USB Emulation option. If you read the description, there is no way one would think that this would have an effect. I changed this to Disabled and that allowed the machine to boot with the iPod plugged in.
I hope this helps someone. If your machines hangs before windows starts, get into the BIOS and go to work!! Tom [email protected]

Dell 1100 laptop Windows XP Dell hangs before windows begins to start

 

My new 5793 hangs up when I forget to unplug my 2.0 GB USB drive out (ScanDisk). I then have to pull it out(which I know isn't good for it). I've gotten pretty good, now, at remembering to eject it as soon as I'm done with it.
Someone suggested that the bios was looking at the usb's first and I should change it in bios to go to the HD first. I'm not real comfortable messing with the bios....yet.

 

That's a good suggestion; did you check to see what the boot order was in the BIOS? It seems to me that the BIOS should never have gotten to the USB as a boot device if the boot order were set so that the BIOS would only look for USB if it found neither an optical drive nor a hard drive.

 

I have had a similar problem, never with my iPod, but with external drives. As far as XP, Vista I don't know, is concerend my usual problem is it attempts to use it as a boot drive, however it obviously doesn't have my boot files.