Screen size compatibility for projection panels

[roger_ush]

Hi all,

I've been wondering for a little while now, before I go and buy a projection panel off ebay, if the specs for a panel say 640x480 am I going to be able to display the full desktop off my laptop which has has a minimum screen size setting of 600x800?

And on a side note, anybody out there looking to sell their projection panel?

Thanks!