Thanks for answering!
But what exactly is the "BIOS EHCI Hand-Off" [Disabled] [Enabled] entry? Should this be enabled with 9x/NT/xp and disabled with xp SP1/xp SP2/ Vista? Or should it be disabled with 9x/NT/xp and enabled with xp SP1/xp SP2/ Vista? Is this BIOS function a workaround? And for what actually??
This is from an ASUS manual (BIOS section):
BIOS EHCI Hand-Off [Disabled] [Enabled]:
Allows you to enable support for OS without EHCI hand-off feature.
I understand that xp SP1 and later have USB 2.0 support. What OS - xp/xp SP1/xp SP2/ Vista - has no "EHCI hand-off feature" as written in the quote above? What OS (xp/xp SP1/xp SP2/ Vista ) has "EHCI hand-off feature"?
And this is from a Microsoft FAQ:
What features of the USB EHCI specification are not yet implemented?
Windows XP supports a number of features in the Enhanced Host Controller Interface (EHCI) specification, but there are a few features that are not implemented. These features may be supported in future releases:
• Features added to EHCI in or after version 0.95.
• Rebalance Lockout (I-Bit)
• Frame Span Traversal Nodes (FSTN)
• 64-bit host controller addressing support. EHCI controller can still work in 32-bit mode on an x64 or Intel Itanium platform.
• Kernel Debugging over USB 2.0.
• EHCI BIOS handoff.
• BIOS vendors should support the EHCI BIOS handoff section in the EHCI Specification for all EHCI-aware BIOS
• Preliminary support for EHCI BIOS handoff will be available in Windows XP SP2. The Windows core team for USB would like to work with OEM partners and BIOS vendors to develop this functionality.