We've finally come to a solution regarding automatic detection of an 80-
pin IDE cable on the PE500SC CSB5 IDE controller.  The patch below 
implements it.  I've tested this with a test BIOS which implements this 
functionality (changes the PCI subsystem device ID as described below), 
with both 80-pin and 40-pin cables, and it works fine.  Based on 
controller type, and max UDMA mode set in BIOS setup, hdparm -i shows the 
maximum speed is properly selected in each case.

Current shipping BIOSs never set those top two bits, so the ide0=ata66 
override is necessary until a new BIOS is available.  The new BIOS is 
projected to be made publicly available in 6-8 weeks.  We're also ensuring 
that any Dell system with a CSB5 follows this same rule.

Patch attached was mailed to Andre Hedrick and Arjan on 8/1/01.