Low Performing SATA HDD

[munnabhai]

I have a Seagate ST380817AS (80 GB 7200 rpm) and i have measured its performance through Fresh Diagnose it is very low.
Read Speed-: 32 MBps as against same model normal is 44 MBps
Write Speed -: 27 MBps as against 31 MBps
I have tried both mode ie. SATA and RAID mode from Bios but the results presists.
What r the reasons for this low performance and how could i improve it.
I have following config.
AMD 64 2800+
ASUS K8V-MX
Seagate SATA

Also I am thinking of upgrading to WINDOWS XP 64 BIT do u suggest that and will i receive better overall system performance with it.

[nishant_nms]

Upgrade to x64 only if u have 512 MB RAM. I had used it on 256 MB. It is slightly slugish than 32 bit XP on 256 MB RAM

[deathvirus_me]

Well ... the speeds are always lower than the actual theoritical speed ..... tell me ... do u find any difference in performance ?? If u do in which apps ???

[munnabhai]

yes its somewhat low in performing in photoediting softwares and some other apps ie. it takes more time to load than my older pata 7200 rpm (seagate).
Also yes i am having 1 GB of ram should i upgrade to WINDOWS XP 64 BIT and from where to get it. Is anyone having that plz tell.