Actually, I have to issues/questions(verified on 2 different pc's):

1) Fresh install of XP (one system running XP-SP3 and 1 running Win2K-SP4) on 2 desktops.
2) Fresh install of latest version of Mach3 demo.
3) Ran Drivertest.exe.  Seemed to run correctly.
4) Showed "Pulsing too slow".
5) Closed Drivertest.exe.  The pc becomes horribly slow.  Slow response and slow to redraw the screen.
6) Started Mach turn.  Configured ports/pins/and tuned motors. (Still slow response).
7) I can Jog just fine.
8  When I try to run any test .nc files, the motors run in 1 second pulses, not smooth like they should. 
9) I have tried the "NoApic" driver, checked the LPT settings.  The "slow down" goes away after a reboot but the motors still run in 1 second "spurts". 

Please let me know where to look or what additional information is needed.  I have run Mach3 successfully in the past off a laptop.  I have searched the forum for a similar problem but haven't found one.

This has got me baffled.....

What are the specs of the computers?
Hood

Unit #1 is:
AMD Athlon XP - 1.5GHz
1GB Ram
40GB HD
32MB AGP Video (Not onboard).

Unit#2 is:
Pentium III - 667MHz
512MB Ram
40GB HD
32MB AGP Video (Not Onboard)

I have been able to run Mach3 successfully (motors working smoothly) previously on a Pentium 2 400 MHz with 512MB RAM with no problems.  I also tested the setup (Motors, controller, pc) under Linux EMC2 and they worked properly.  I haven't turned off the ACPI service in Windows.  That's my next step to try.

Can you attach your xml please and I will see if I can find an issue there.

Hood

Thanks for taking a look at this for me.  I have attached my XML file.

I have sent you a private message.
Hood