I’m getting tempo lag when using Grid Pie, when too much data is copied at once I guess. Is there a way to set priority so there won’t be any lag or glitches?.. I wouldn’t mind if copying is a bit slower while playing, as long as tempo and MIDI is solid.
I tried all the XP optimizing tricks, with moderate results. Still getting a noticeable increase in CPU. I guess Renoise isn’t really designed to copy/paste while playing?
I generally find XP isn’t designed to do much with only 1GB of RAM… Not sure how well the Pentium M 1.7GHz is really going to perform either. Don’t think suggesting a new laptop is really going to be very constructive though! 
Yes, I know. Just have to work with what I got. Can’t afford a new laptop now. Since I work mostly with MIDI it is usually good enough. I can launch clips in Ableton without a glitch, but Grid Pie is a hack that uses copy/paste, which I guess isn’t the optimal way to do it performance wise.
The desktops here at work are old P4 machines and as standard have 512MB of RAM in them (managed to upgrade the one I use to 1.5GB, although it is original DDR whereas some of the others are DDR2, hence why it used to be the worst.) Just trying to change the program you are viewing, eg from Outlook to a pdf in Acrobat Viewer, used to take a few minutes, no exaggeration. Although with triple that RAM it is almost usable for general browsing and work based stuff I don’t think I’d want to try anything audio on it!
As you mainly do MIDI stuff have you considered using a lightweight Linux distro? Something I would definitely consider with a computer of those specs.
I don’t think my soundcard is supported in Linux. And I rely heavily on Bidule, not too sure how that would work out, also not sure about Linux support for my Monome… I’m guessing being forced to run things through Wine would eat up any performance improvements?