Strange harddisk performance problem...

[ichtys|dk]

I've installed Gentoo Linux for my first time a couple of days ago, but one thing is not working proberly...

My harddisk runs very slow, and it's pretty obvious that it has an effect on the whole system.

I've tried to recompile the kernel to ensure DMA support, but it doesn't change a bit.

I've run hdparm -X69 -c3 -m16 -d1 -u1 /dev/hda, and now hdparm -tT /dev/hda gives the following result:
/dev/hda:
Timing buffer-cache reads: 352 MB in 2.02 seconds = 174.26 MB/sec
Timing buffered disk reads: 10 MB in 3.42 seconds = 2.92 MB/sec

I've enabled DMA and everything... but still it works this slow...

What can I do, to improve the harddisk performance?