SATA drivers for 80821 (ich7) controller

[vojans]

Hello all,
I'm having a "challenge" finding solution for sata driver or any solution without recompiling the kernel (Red Hat Ent. Linux 4 Upd. 3)
The machine is a remote one (and that is the biggest problem), some Z intellistation as I recall (I'll try to ask somebody for the exact model), which has SATA drives which work in "compatibility" mode, as hdX, not sdX - I think it's ICH7 controller, can't check it now (if needed, I'll check it tomorrow).
hdparm says, as I experience, 4 mb/s instead of at least 10X more.
There are some errors in /var/log/messages which gave me a clue that drives are not performing well because of wrong driver, and setting dma in hdparm is of course "not permitted".
Suggestions, anyone?
Is it possible to recompile a module or something, and do an insmod?

[vojans]

Here are some new informations:

lspci | grep IDE

00:1f.2 IDE interface: Intel Corporation 82801GB/GR/GH (ICH7 Family) Serial ATA Storage Controller IDE (rev 01)

lsmod (last part of it)

ata_piix 11973 0
libata 66057 1 ata_piix
sd_mod 19393 0
scsi_mod 140561 2 libata,sd_mod