Every once and awhile the computer freezes (mouse does not move, Mach3 stops, etc.) when running g-code through Mach3 to my CAMaster CNC machine. At first I thought it was a hardware issue, so I replaced the entire PC with a faster PC with more memory (2.66 GHz Intel with 1gb RAM) but am still experiencing problems. Yesterday while cutting, the computer/Mach3/CNC would freeze for 5 to 10 seconds and then unfreeze and resume normal operations. This happened 3-4 times in 5 minutes. With the old computer, it would freeze and never unfreeze which would require a hard boot.

I even had the computer freeze permanently when I double clicked the Mach3 icon and then flipped the ON switch for the CAMaster CNC machine. I remedied that problem by loading Mach3 first, then turning on the machine. But even then, that shouldn't happen?

When the CNC is running, the only program running on the computer is Mach3. During this time the computer is also wirelessly connected to the internet but no browser is loaded. I am running Windows XP Pro which was freshly installed not even one week ago.

Any ideas?

try running the code cutting air but without your spindle running, it sounds like electrical  noise is killing your computer.
Hood

My CAMaster MC2840 uses a Porter Cable router.

It's tough to diagnose the problem because I cannot replicate it. I'd say 80% of the time it works flawlessly while the other 20% has a glitch here and there. I'm going to try http://www.machsupport.com/downloads/XP_Optimization.txt to see if any of those suggestions prevents future occurrences.

Also, like I mentioned in the first post, it froze on me when loading Mach3 and turning on the CNC machine. No g-code or the router itself was running.

Still sounds like noise and/or possibly a power problem, when energising the machine  the transformer may be causing a surge.
What

Still sounds like noise and/or possibly a power problem, when energising the machine  the transformer may be causing a surge.
What

What would be the remedy?

If possible as a test try powering the computer from a different source.
If its noise then shielding and grounding properly is really the only cure.
Have a look at the CPU usage when using the machine and see how that looks.
Hood

If possible as a test try powering the computer from a different source.
If its noise then shielding and grounding properly is really the only cure.
Have a look at the CPU usage when using the machine and see how that looks.
Hood

Unfortunately everything in the garage is run off of one breaker.

You're talking about grounding the CNC machine, correct? How would I ground it? The table is steel and rests on a concrete floor.

I am meaning your machines control hardware, not sure what its like at the moment but if the cables are shielded they should only be grounded to one point in the cabinet and all other shields should also ground there.
Do you have any pics of your machines control cabinet that you could post?
Hood

I am meaning your machines control hardware, not sure what its like at the moment but if the cables are shielded they should only be grounded to one point in the cabinet and all other shields should also ground there.
Do you have any pics of your machines control cabinet that you could post?
Hood

Yes, but I'll have to get those online later this evening.

I like to recommend a line filter on spindle motors to keep the electrical noise they generate from getting back into the control and PC and causing problems. I carry a 10A unit here: http://soigeneris.com/cncparts2.aspx , if your spindle motor draws more than 10A you should be able to find a similar unit with a higher current rating. Also, if your switching you spindle with a relay you should install an arc suppressor across the relay contacts.