Michael Barnwell wrote:

I'm experiencing silent data corruption
on my RAID 5 set of four 400GB SATA disks.

I have circa the same hardware:
 * AMD Opteron 250
 * Silicon Image 3114
 * 300 GB Maxtor SATA

Just to add a data point, I've run your test on my RAID 1 (not RAID 5
!) without problems.

localhost ~ # dd bs=1024 count=10000k if=/dev/zero of=./10GB.tst
10240000+0 records in
10240000+0 records out
localhost ~ # od -t x1 ./10GB.tst
0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
*
116100000000
localhost ~ # uname -a
Linux localhost 2.6.12.6-xen #6 SMP Fri Jan 6 06:49:53 CET 2006 x86_64
AMD Opteron(tm) Processor 250 AuthenticAMD GNU/Linux