never to use your buildin hardrive as scratch disk?

[sheriffg]

Hi,

When I first bought my Macbook pro, in 2008, the Mac Sales guy told to not use my hard drive as the scratch disk. He advised to use an external drive as a scratch disk.

I told him that I would be making videos using Final cut express.

So I've always used an external drive, but it takes a HUGE amount of time to export videos or render videos.

I didn't think much of it as I thought that's normal, but I discovered that it was much faster to use my built in hard drive as a scratch disk.

So I'd like to use my hard drive as the scratch disk and then transfer my work to my external drive when I'm done.

Is the warning of not using my hard drive as a scratch disk a good warning. Should I follow that advice?

[juststarting]

Buy a 500G internal drive for around $49 and use it as your scratch disk along with additional storage, then your main drive won't be reading and writing constantly.

[jagabo]

Putting a second hard drive in the CD/DVD bay is a good idea. You don't need the CD/DVD drive when editing. External USB drives are limited by the speed of the USB port.

[edDV]

The idea of separating the scratch disc from the OS disk is sound but depends on your workflow.

The OS, in this case the Mac OSX has priority on the internal drive and other things being equal, it is better to separate the scratch disk and video capture files from the OS drive. If it was a desktop, a second internal drive would solve the issue. Jagabo's solution is similar.

External drives vary in speed. USB2 is slowest, Firewire 400 next, then Firewire 800. A PC or mac Pro tower would offer a eSATA solution that is just as fast as an internal drive.

I'd separate functions this way. For capture of DV or MPeg2 on a current dual core MacBook, the internal drive can be used but you need to verify the OSX didn't trash the capture. Odds are better with a dual core CPU. Capture for less compressed formats, it is best to avoid a laptop at all.

Once video is captured, there is little chance of data loss. It comes down to data throughput and CPU speed. In most laptop cases, CPU speed dominates.

The scratch disk stores tmp files during timeline renders. The difference in speed between a "slow" 5400 RPM USB2 drive vs. a "fast" 7200 RPM internal laptop drive has little effect vs. the CPU time required to calculate the tmp file. Don't expect drive speed to have much effect.

If you were using a dual quad core Mac Pro tower (8 cores not 2), the disk system speed may have a significant effect.