I have checked the performance data from hdtach 2.7 with my drives and the average value is pritty much the same as the value
hdparm -tT delivers.
By the way, I do not trust all the values hdtach delivers.
I think that for a 20 GB drive 29 MB/s is a very good value.
Here for comparison
Seagate Barracuda 7200 rpm 120 GB: hdparm 37.64 MB/s hdtach: max. 45.5 MB/s min: 15.2 average: 36.0 MB/s
Seagate Barracuda 7200 rpm 200 GB: hdparm 61.24 MB/s hdtach: max. 65.5 MB/s min: 35.4 average: 58.0 MB/s
Bigger drives have a higher data desinity so with the same angle speed (7200 rpm) you simply read more data
within one rotation, that's why bigger drives have a higher sequential throghput.
keep in mind that you have 20 GB which is about 1/6 of 120 GB.
Still if you think that you can achieve even higher throughput take a look on your settings either with:
a) hdparm -I
(you may also take a look on the hdparm manpage: man hdparm)
b) cat /proc/ide/ide0/hda/settings
As for the sound:
1) Check if your card is ALSA supported:
Find there your card and click on the Detail Field. There are some additional explanations.
2) It may be that your ALSA Version does not have a native support for your card.
Take a look on the lsmod output. The ALSA card drivers start with snd_
snd_ac97_codec 55556 1 snd_emu10k1
I have a Creative Soundblaster Live and the driver is snd_emu10k1.
3) Enable ALSA Output in xmms and check if it plays:
Right Click on XMMS Windows and then:
Then select as output plugin: ALSA
Restrat then xmms
4) It may also be that your aRts (the default KDE Soundsystem) has problems with ALSA