Promise SATA controllers & FreeBSD-7

Well, its been almost 2 months since this was last mentioned (unless I
missed something), and nothing appears to have moved since, well, the
problem first appeared many months prior to that.

So as the branch for -7 is (hopefully) approaching, I thought I'd see if
anyone had any news or ideas on this rather irritating problem.  Of course
the main reason for my post is entirely selfish -- I'd like to experiment
with ZFS, but system instability caused by even moderate disk usage is
hardly conducive to worthwhile testing...

I, too, am seeing the now infamous:

adX: WARNING - READ_DMA UDMA ICRC error (retrying request) LBA=...

messages after simple commands like (cd /usr/ports; make search key=bonnie)

In my case, ad4 and ad6, connected to a Promise PDC20579 on-board SATA
controller.

This system has been essentially entirely stable whilst running 6-STABLE
for the past several years.

To me, this is a serious problem which will stop me from using FreeBSD-7.

If there is any way to help diagnose this problem, I'm willing to give
what assistance I can, but I'm not too sure where to begin...

Alternatively, if anyone can recommend a cheap PCI SATA card which is
known to work well with FreeBSD-7, I might just end up buying that...

-- 
David Taylor