Virtual Memory

[Chris]

I'm currenty running 256MB of RAM and are about to put in some more as for editing videos its very slow and the playback is jerky, and eventually when a lot of clips are being played, the program I'm using crashes.
I've heard about virtual memory where the computer assigns some of you hardrive to be used as RAM. What I am wanting to know is is there thing to stop me from setting my virtual memory to say 3 or 4 GB's of my hardrive? If not, how about 10 or 20GB? Wouldn't buying more RAM be pointless when instead you could buy a 40 or 80GB harddrive and set it up so all of it is used for virtual memory.
There is obvousliy a reason why it can't be done or else everyone would be doing it. I would be intreasted to know what it is.

[Marc Peters]

I believe the default setting is 1.5 times your installed RAM. Some say that with 1GB and over, you don't need a paging file. Some say you do. Essentially all you need to know is that letting Windows handle the size is fine.

http://www.theeldergeek.com/sizing_the_page_file.htm

[tongachutt]

Increasing your virtual memory size will never make up for a lack of RAM and will certainly not help when it comes to video editing. A 10 or 20 gig page file will probably slow your system to a crawl as your PC will spend the whole time reading/writing data to disc, and managing such a large pagefile will cane what little RAM you have already!

The difference between RAM and pagefiles is speed, remember any data that is fed to the CPU must first be in RAM so data needed from the pagefile is "swapped" from the HDD into RAM before processing. Hard drive access times are measured in milliseconds, RAM access is read in nanoseconds = bottleneck.

Get at least 512Mb ram for video editing, more if you use a beefy NLE like premier or Avid etc..

Tonga