I've got what may be a hardware or architecture issue that I'm at a loss
for even where to start looking.

I'll start with some questions. Hopefully the answers will show me the
error of my ways.

1) Will SATA drives and interfaces work with whatever speeds are
available and negotiate? In other words, if a drive (or 2) are different
speeds than the speed of the controller (capability) will it still work
well (via negotiation), or do they have to match.

2) Will a SATA controller support more than 2 channels, or is it
possible to design it such. That isn't possible with PATA master/slave.

3) With XP, if one used Linux (clonezilla for instance) to clone the
first drive (C), then installed it as a second (D), both vol IDs would
be the same. This works (in other words, it boots and reads/writes) but
will the system exhibit transient problems, conflicts, etc?

In a nutshell, the system in question has 2 SATA drives of a faster
variety than orig. It appears to have 4 channels on the primary
controller (CD is on it too), and all works well until the second cloned
drive is on for a while. Eventually some access causes it to drop one or
both drives out of DMA mode to PIO mode. This indicates windows got an
error reading. I've just tested #3 by changing the drive ID, but no joy.
Perhaps someone has greater insights on this?

It could be a limitation of the architecture of the particular hardware
design perhaps, a speed issue, a vol ID issue, or something else. It
might also be a spinup issue. Both new drives are from the same mfg as
the orig, but are 3Gb/s rather than the orig 1.5Gb/s.

BTW, DMA mode gives about 100+MB/s performance, PIO <8MB/s. It isn't an
option...

Does this sound familiar to anyone? ANY pointers as I grope around
without bus analyzers or driver source code?

Thanks in advance.

-Skip

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