External hard drive problem

[Pete]

I have posted this also to alt.comp.hardware but given this may be a
windows XP issue, I am also posting it here. Thanks for your help.

Hi,

I just bought a 200 Gb external firewire/USB 2.0 hard drive in a 3.5"
case for my standalone Dell notebook. Although it worked flawlessly to
back up my data, when I run some tasks like intensive processing of
images on this drive and even the Windows XP defrag utility, the hard
drive stops working and disconnects itself. I then have to switch it off
then back on again to get it to reappear under My Computer. When ever
this happens, Windows XP reports this error:

"Windows - Delayed Write Failed
Windows was unable to save all the data for the file G:????. The data
has been lost. this error may be caused by a failure of your computer
hardware or network connection. Please try to save this file elsewhere."

I'm reasonably clueless about what to do in these situations but I did
run the Windows XP disk error checking utility (which took literally a
couple of hours). This did not report any problems.

I'm wondering what might be causing this annoying problem. Is there some
hardware settings I need to tweak or is this likely to be a bad disk
drive? I should say that I'm using the firewire port. My other option is
USB 1.1.

Thanks for your help.

 

[Alex Nichol]

"Windows - Delayed Write Failed
Windows was unable to save all the data for the file G:????. The data
has been lost. this error may be caused by a failure of your computer
hardware or network connection. Please try to save this file elsewhere."

I'm reasonably clueless about what to do in these situations but I did
run the Windows XP disk error checking utility (which took literally a
couple of hours). This did not report any problems.

The best thing in such a case is to turn off the delayed write - the
loss is not in practice very much and better have it work reliably. Go
to
Control Panel - System - Hardware - Device Manager
look for the drive, double click and in the Policies page uncheck
'Enable Write caching'

I would also go to the USB controllers section, lower down and look
for the USB Root Hub that shows as being in use for this device on its
Power page. Then in its Power Management, uncheck 'Allow computer to
turn off to save power', which may well be the underlying cause

 

[Pete]

Thanks Alex,

I am using firewire, so I didn't employ your USB suggestion, however
both enable and disable write caching produce the same error. This is
very evident if I try to defragment the disk (not that it needs
defragmenting). About 30 seconds in after a lot of thrashing, the disk
falls silent for 20 or so seconds and then I get the "Windows - Delayed
Write Failed" message.

I found a MS article (Article ID : 330174) on this with your suggestion
the third option as follows:

1. Make sure that your UDMA hard disk controller is using an 80-wire,
40-pin cable. For information about how to do so, view the documentation
that is included with your computer, or contact your UDMA hard disk
controller manufacturer. Test to determine if the issue is resolved. If
the issue is resolved, do not complete the remaining steps. If the issue
is not resolved, go to the next step.

2. Warning Do not change your BIOS settings unless you are very familiar
with all the effects of changing BIOS settings. Make sure that your BIOS
settings are not configured to force faster UDMA modes. For information
about how to do so, view the documentation that is included with your
computer, or contact your computer manufacturer. Test to determine if
the issue is resolved. If the issue is resolved, do not complete the
remaining steps. If the issue is not resolved, go to the next step.

3. Turn off the "Enable write caching on the disk" feature.

I searched my Bios and couldn't find any reference to UDMA (?) and
wouldn't have a clue about an 80-wire, 40-pin cable issue.

Can you help out with either of these two MS suggestions ?

Is it likely a problem with the new external hard drive?

Thanks again.

 

[Pete]

Now, here's the thing:

When connected using Firewire, I get the problems reported when trying
the defrag but using USB 1.1 I don't. Well, at least I think it's 1.1
but it doesn't seem much slower than Firewire, if at all, which I think
is strange.

Does this offer further clues?

Also, is there a way to check whether I have USB 1.1 vs USB 2.0?

Finally, is there a way I can properly test the speed of the drive
running USB versus Firewire - like a diagnostic tool I can download
somewhere?

Thanks again.

 

[R. McCarty]

If the device is USB 2.0 capable and you plug it into a USB full
speed port (Version 1.1) XP will report that a USB2.0 (High Speed)
device is being used in a non-USB2 port.
Determine USB capability by the descriptor in Device Manager
for Universal Serial Bus Controllers by checking for "Enhanced
Controller" - which denotes USB Full Speed 2.0.
For benchmarking, I would use DiskSpeed 32 which can display
the important aspects of Burst, Sustained transfers and access time
- which shouldn't vary between Firewire and USB.
Disk Speed can be downloaded from:
http://www.geocities.com/vgrinenko/DiskSpeed32/

 

[Pete]

Thanks R.,

In Device Manager under Universal Serial Bus controllers I have 8
entries:

Intel(r) 82801DB/DBM USB 2.0 Enhanced Host Controller - 24CD
Intel(r) 82801DB/DBM USB Universal Host Controller - 24C2
Intel(r) 82801DB/DBM USB Universal Host Controller - 24C4
Intel(r) 82801DB/DBM USBUniversal Host Controller - 24C7
USB Root Hub
USB Root Hub
USB Root Hub
USB Root Hub

and if I plug my external drive in I get another entry:

USB Mass Storage Device

Does this smean my 2 x USB ports are 2.0?

Thanks.

 

[R. McCarty]

Yep - That's how most Intel Chipset 82801 Controller Hubs are
enumerated in Device Manager. Your PC should have 4 fixed USB
ports on the back plane, then two separate connectors. One for use
with front panel USB ports and the other to a PCI slot access.
Unfortunately, there isn't a software tool for diagnosing which type
of USB (Full -1.1 or HighSpeed 2.0) are present. Adaptec has one
called USB Control but it only works with Adaptec PCI Add-in USB
cards.

Also, the ports aren't logically arranged - You need to change the
Device Manager default view to "View by Connection", then expand
the ACPI, ACPI Compliant System, PCI Bus, USB hubs and you can
see how actual devices are connected to which HUB by their identifier
(24C4, 24C2, etc). In other words USB ports 1 & 2, 3 & 4, 5 & 6
don't always equate to the same Hub. It's confusing, but helps if you
have a heavily loaded HUB where power limits or bandwidth are
an issue.

 

[Pete]

Thanks for that, but I remain confused. I have a Dell notebook and only
have two USB ports. Doers this mean they are both USB 2.0 based on the
info I provided above or just one of them?

I have done some tests of read/write/and random access speeds for the
USB 2.0 (?) port versus firewire. (It is only when I use firewire that I
get the "Windows - Delayed Write Failed" problem). I'd welcome your
feedback:

Firewire
----------
Sequential Write: 22.4 Mbps
Sequential Read: 29.4 Mbps
Random Access: 16.7 Mbps

USB
----------
Sequential Write: 23.3 Mbps
Sequential Read: 24.3 Mbps
Random Access: 12.8 Mbps

Are these fairly typical rates?

Thanks a million.

 

[R. McCarty]

I wasn't aware that your PC was a notebook. In that case, then
both USB ports are 2.0 (High Speed).

As to the Firewire connection experiencing Delayed write failures
it could be due to the Polices on the drive. I have a Maxtor external
USB drive. Whenever it is connected, it's Device Manager policy is
set to "Optimize for Quick Removal" which doesn't use delayed writes.
You should connect via both technologies and go to Device Mgr &
click the Policies Tab and see how the caching is set in each setup.
Perhaps when you use Firewire, the disk cache can't flush data fast
enough and that's why you are getting the error.

 

[Alex Nichol]

When connected using Firewire, I get the problems reported when trying
the defrag but using USB 1.1 I don't. Well, at least I think it's 1.1
but it doesn't seem much slower than Firewire, if at all, which I think
is strange.

Does this offer further clues?

Also, is there a way to check whether I have USB 1.1 vs USB 2.0?

If it is much the same speed, it is probably USB 2.0; check in Device
Manager, in USB Devices to see if it refers to USB Enhanced controller -
that means USB 2.0, and d-click and checking Drivers, details, should
show it using usbehci.sys

Why there should be trouble on Firewire and not USB I can't be sure, but
suggests something dicey in the Firewire hardware, either machine or
device end

 

[Pete]

Hi Alex,

I do have usbehci.sys and now I am convinced I have 2 x USB 2.0 ports.
That's good news. I might shoot off to the Dell forum to see if similar
problems have occurred.

Thanks for your help.

 

[Pete]

Thanks, you've been a big help. I have tried to alter the policies
without a change in the problem. I have just posted to the Dell
peripherals forum. I don't think I am alone in having firewire problems
it seems.

One FINAL question: do the read/write speeds I reported sound within
normal limits?

Again, many thanks.

 

[R. McCarty]

I would visit the Drive web-site and pull the product specifications
sheet (probably a .pdf) and check the "Rated" speeds. But yes the
values you mention track with what I see on my USB 2.0 External
Maxtor. On my 5000-LE the access time is around 20 mSeconds
and average Read/Write data rates are around 17-20 Megabytes.

 

[Pete]

Again, thanks.

 

[Pete]

Just for completeness-sake...strangely it seems this is a problem with
virtual memory. I changed the min and max values to 1.5 times my RAM
(512 Mb) and now the drive appears to work properly. I just did a
successful defrag, something I wasn't able to do previously using
Firewire. I will do some more testing tomorrow, but it looks promising.
The help came from the Dell forum. Yippy !

 

[R. McCarty]

Thanks for posting - Always good to hear when someone finds a
solution and helps the next person researching a similar issue.