Hi all,

My laptop has SATA, in particular lspci says it is :

00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7 Family)
Serial ATA Storage Controller IDE (rev 02)

I found that when I recompile the kernel I can get it to boot
using these settings:
CONFIG_BLK_DEV_IDE_SATA=y
# CONFIG_BLK_DEV_HD_IDE is not set
CONFIG_BLK_DEV_IDEDISK=y
CONFIG_IDEDISK_MULTI_MODE=y
CONFIG_ATA=y
CONFIG_SATA_AHCI=y
# CONFIG_SATA_SVW is not set
CONFIG_ATA_PIIX=y

But the performance is very poor.
When the system starts up, it says that DMA for SATA is disabled,
and I tried using hdparm to turn it on but it gives an error.
According to hdparm -t. buffered reads are only 1.5 MB per second.
This is less than USB, in fact.

Can anyone explain what is going wrong and how I might fix it?
Note that the precompiled kernel is just as bad.

Thanks.