WPF performance and Tablet / UMPC type PCs

I am trying to develop innovative applications for Tablet PC and UMPC users.

Generally speaking these types of machines will not be powered with the latest 3.0Ghz+ dual processors etc. For instance my machine is a 1.4Ghz Intel Centrino with 512mb RAM. It has a tier 2 capable GPU, i,e, dxdiag shows that the GPU supports DirectX V9. I am running Windows XP Tablet PC 2005 edition.

I have been playing with the .NET 3.0 WPF RC1 build (and at this stage I am not even using digital ink) just trying out various presentation ideas. The problem is that although the features are great - the performance is frankly, awful

My problems begin when I try to display a WPF page with more than a few elements on it.

For instance, imagine trying to present a simple Excel style worksheet with rows, columns and cells. There are lots of ways to go about creating a page like this in WPF (e.g. Grid, ListBox, GridView, ScrollView controls with Border, TextBox, Line content), but you usually end up needing more than a 1000 elements visible at any one time to represent the cells.

Whatever I try, I seem to end up with the same result - high CPU utilisation (75-100%) and slow response time (seconds) whenever a UI action is initiated which affects the visible content e.g. scrolling down one row.

I have checked that DirectX is utilised by using the Perferator tool. I am only creating and using the number of elements required to fill the visible area i.e. I am 'virtualising' the input data.

Back tracking, I have also realised that even simple examples e.g. a ListBox which displays a list of names with a border around them can use 100% CPU when scrolling! The scrolling is really slow.

The thing is, reading through the forums I suspect I am not the only one who is suffering from these types of problems.

Looks like its back to Windows.Forms / GDI . . .