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Use of Expresscard Drive as CS4 Scratch

Paul2660

Well-known member
I would like to use a 32GB Expresscard drive as a scratch drive for CS4. Environment is windows7 64 bit. Windows see the
drive as a removable drive. When I go to CS4 to select it as a potential scratch drive, the drive is not listed. I am assuming this
is because windows has the drive loaded as removable and not a Local hard drive.

If you take any standard USB external drive and plug it in, CS4 will see that for scratch since they load as local drives.

I understand that before the expresscard technology a "removable" drive would be too slow for scratch, but shouldn't the
speed of the expresscard slot be enough?

Is there any setting in CS4 to allow it to accept removable media? or a way to make windows see it as a local disk?

Thanks
Paul Caldwe
 

Bob

Administrator
Staff member
There are some good reasons why you might not want to use flash memory as a scratch drive.
First, scratch is a write-mostly drive which is used at the point where there is a image memory shortage, particularly history. Flash memory is usually slowest to write and faster to read. Additionally, flash memory is write-cycle life-limited and not designed for a large number of writes. What you probably want is something that is fast on writes, such as an internal hard drive.
-bob
 

Paul2660

Well-known member
Bob:

Thanks for the info. Here is how I understand the SSD for the expresscard slot.

The SSD is a hard drive not a flash card, ie memory. As I understand it, the Express slot SSD is no different than any other Solid State hard drive. From what I have read about performance, SSD's are over all better than standard hard drives. Most companies now offer a SSD as an option for the primary hard drive. The expresscard SSD shares all of the same speed and performance benefits of the 2.5 SSD.

Thus it should have the same features as a hard drive and not be seen as memory as a Compact flash card would be. This is based on the articles I have read up till now.

More important, I would still like to try it and see how it performs.

Paul Caldwell
 

Bob

Administrator
Staff member
Most older design ssd drives are not reasonably usable as scratch.
In fact, I am using right now a notebook computer configured with both an ssd as its boot drive as well as a hard drive which I have configured as scratch.

The ssd is a crucial brand 256 MB model with read and write specs of 250MB/s and 200MB/s respectively

the transcend expresscard ssd, for example has read and write speed specs of 35MB/s and 25MB/s the OCZ reads at 18MB/s and writes at 12.5MB/s

I think that Verbatim is speced at 125MB/s read and 30MB/s write

Hard drive average read and write performance, using the Hitachi 7K500 is 83MB/s.
Since PS scratch depends on the write speed even more than the read speed, unless your expresscard is writing faster than the hard drive, it will not gain you much if anything.

Perhaps there is a different express-card ssd you are looking at?

Given those performance specs I wouldn't bother.

As for writes on ssd, until recently even the best commercial ssd's suffered from significant performance degradation in the neighborhood of 20% due to internal management of write-leveling algorithms when they had been written to excessively. There are now beginning to come to market some better ssd drive controllers that perform wear-leveling operations during times of inactivity. Nonetheless, ssds of all stripes today sill have the potential for wear-out due to excessive write activity which is what the wear leveling is all about, that is to spread writes out to different locations on the drive so that one set of cells are not taking all the punishment.
As far as making your machine and PS recognize the expresscard as an external drive worthy for use as scratch, perhaps it knows something :angel:
-bob
 
Last edited:

Paul2660

Well-known member
Yes, I didn't look into the speeds as well as I had thought. I have the transend 32GB and it does appear to be considerably slower than I realized.

I had also not realized about the repetitive writes to SSD's before but after reading your post, did more more web searches. Looks like the SSD has a few more iterations before it gets to the best performance.

Thanks again
Paul
 
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