Tablet PC performance issues

I have a Thinkpad Tablet PC running Windows XP Tablet PC 2005 SP2 on a 1.6Ghz Pentium M CPU with 1.5Gb RAM. It has performance problems which are continuing to occur after rebuilding from scratch.

Frequently, the CPU is pinned. Microsoft Outlook runs terribly, often Not Responding especially with selecting emails that have attachments. Opening Word and Excel attachments is further very slow. Other applications open very slowly like IE which also can get hung up/Not Responding. The cursor on the desktop is very jerky when applications are opening.

Are there other folks experiencing similar performance issues?