USB 2.0 Storage Slow when Inserted, Fast after Reboot. Huh?

  • Thread starter Thread starter wernst
  • Start date Start date
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wernst

All,

OK, here's a head-scratcher. I have two USB 2.0 SDCard card readers;
one from SanDisk and one from Crucial. The computer in question is a P4
@3 GHz on an Intel 865-based mainboard running Windows XP SP2 that is
otherwise working great.

When Windows is running and I insert an SDCard into the reader, or if I
insert the card AND THEN plug the reader into any USB port, the
transfer speed is slow -- something like 3.5 minutes for 170 MB. There
are no "unknown" hardware items in the Device Manager when this
happens, and windows doesn't complain about plugging a high-speed
device into a low-speed USB port.

However, if I reboot (or turn the computer on) with the card/cardreader
ALREADY plugged into a USB port, I can transfer the 170 MB of files in
20 seconds or so. The drive letters are the same as if I had plugged in
the device after booting.

I troubleshoot computers for a living, and I've already tried many
things to no avail:

1. Updated the USB drivers for the 82801EB Host Controllers to Intel's
latest and greatest. No change.
2. Unplugged every USB device except the card readers. No change.
3. Disabled any background software that uses USB hardware (like webcam
or gamepad background software and drivers) except iTunesHelper.exe (I
use a firewire connection for the iPod. FYI.) No change.
4. Tested the cardreaders in other Intel-based computers with SP2.
High-speed transfers work immediately on these other computers.

This certainly sounds like a software issue, since the cardreaders can
work at high speed when they are inserted before the boot process, but
I'm at a loss to track down what's going on.

Has anyone here ever seen this? Any suggestions?

Thanks,
Warr
 
Jaymon,

Thanks for taking the time to respond.

The Intel utility says "This system has FULL support for USB." The
details screen shows that no updates are required.

The SanDisk and Crucial products have NO drivers for Windows XP, as XP
supports such devices natively.

The SanDisk link stating this is:
http://www.sandisk.com/Retail/Default.aspx?CatID=1114

The manual that comes with the Crucial product says the same thing.

I'm going to test other USB devices later tonight (ipod, external hard
drive, USB keydrives) and see if they act the same way. I'll report
back with the results.

-Warr
 
All,

Just a followup.

My various USB thumbdrives, ipod with USB connection, and external USB
hard drive all transfer at full USB 2.0 speeds whenever they are
plugged into the PC. It is apparently *just* the cardreaders that are
displaying this weird issue.

This therefore becomes merely a minor hassle instead of a major
problem, but I still wouldn't mind knowing what the solution is. If
anyone else has any ideas, let me know.

-Warr
 
Hi,

Disconnect the card reader first.
Try run regedit and navigate to

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Enum\USB\Vid_xxx&Pid_xxx
click to open the Vid subkeys one by one and look at the right pane to find
the card reader under the Data column. when you found it, delete the whole
Vid keys and then exit regedit and then reboot.

Replug the card reader to a USB 2.0 port and test the speed.

CARE: backup the registry before any deletion for just in case.

Hope it hepls
 
Peter,

Well, I found and deleted the registry keys in question. Restarted.
Tried the hardware.

Re-recognised (good) but no change in speed (bad).

I have an article to write today, but I'll give those other utilities a
crack later in the week.

-Warr
 
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