Extremely slow disk transfers with SATA disks

[chrism at imntv.com (Chris Mauritz)]

Vanja Hrustic wrote:
> I have installed CentOS 4.2, recently, on new computer.
>
> Everything seemed to work fine.
>
> However, we've found out that disk transfers are incredibly slow, and I
> just can't figure out what to do in order to fix it.
>
> Computer is now running CentOS 4.3 (updated it 1 hour ago), and same
> thing is still present. I hoped kernel upgrade might fix it, but it
> didn't.
>   

I am having similar issues with an Intel 845 based board.   It sounds 
like your disks are running in PIO rather than in UDMA mode.

Have you tried:

hdparm -d1 /dev/sdX

substituting the actual device names for each drive?

I was unable to remotely fix mine, but plan to visit the machine soon 
and fiddle with bios settings to see if I can get the drives out of PIO 
mode.

Cheers,