The actual recording time should be about the same with your CPU and some 2+ GHz CPU.
What will change is the ENCODING time. It's very linear to CPU power. If you had a twice as fast CPU, it would take 1/2 as long.
Any under 1,000 buck desktop will do this much faster but none (at that price) will break it down in less than say, one hour.
Bob
I have a 566MHz processor. Ive tried to burn a dvd but holly it takes a like 18hours. and thats just a 1 GIG of video. Im guessing not even if i upgrade it wont make a difference. So my question is which comp or kind of computer can help to burn this kind of video.

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