View Full Version : Suggestion for HD - Scratch setup

03-20-2008, 10:08 PM
I just purchased a 2.8GHz Mac Pro 8 core with basic setup; a 750 GB Seagate Barracuda 7200.11 and add'l 8GB RAM are on their way from MacGurus. I use Photoshop and Aperture a lot. Some files in PS are 300-500 MB. My old computer is a G5 dual 2 GHZ, 2.5 GB RAM, 250 GB HD. So, nice step up for me.

Until I can afford at least one more Seagate HD, I will be using the 320 GB that comes standard from Apple. I would like a scratch disk for PS.

Do you recommend setting up the new Seagate drive as my main drive, loading the OS, software, and files on it and using the 320 GB HD as the scratch drive? Is there a better way to configure my system with this HD setup? I do NOT have a RAID card nor can I afford one right now. Any suggestions and information on what needs to be done would be appreciated.

2nd question: What do you recommend for a disk utility program? Is Micromat TechTool Pro a high-end tool?


03-21-2008, 09:49 AM
A RAID card is an expensive non-necessity. In particular the Apple MegaRAID card is not very fast, is very expensive, and takes up the internal drive bays. In my opinion, for what it is worth, a hardware RAID card should be external port these days allowing use of the internal bays for dedicated purposed drives.

That said, again in my opinion, if you want a RAID for scratch disks nothing is faster than just using Disk Utility to create a RAID0 from two or more hard drives. It is totally a waste of a hardware RAID card to use it to make a simple scratch RAID. The real reason you would want a hardware RAID is to run a more complex RAID type for a bit more secure data storage. No reason to make a more secure, and slower, scratch disk on a hardware RAID since it only stores temporary files.

Now to the questions you asked.

First off, the 320 GB drive that Apple is shipping is an older model Seagate drive. That drive is not very quick in comparison to current models. However, it will do fine for now as a dedicated scratch disk. Eventually you may need to replace it with something faster.

For now, that is a good plan, The gain to a faster drive later is not huge, but will be noticeable. You may also decide to add a pair of really fast drives in a RAID0 to make you scratch disk faster yet. We'll all be happy to help you decide when the time comes how to implement the best strategy for your needs.

You don't mention what your backup drive is currently. You must have a backup for your DATA. No way around it.

Best utility for maintaining your data is Disk Warrior from www.alsoft.com That is the only one most of us use around here. TechTool tries to be all things and ends up really not doing any of them very well.


03-21-2008, 02:00 PM
Thanks for the response and advice.

Backup - I have two, 250GB LaCie firewire external drives that I currently use for backup; one on-site and one off-site. Down the road I plan to get an external multiple HD enclosure for backup. I like the concept of the Drobo, but it doesn't have firewire so I am thinking of a MacGurus Burly enclosure.

For implementation of what you suggested; is this the correct process?

Install Seagate drive and "zero out" as described in "Preparing New Drives".
Transfer OS from shipped HD to Seagate (what's the best way to do this?)
"Zero out" the Apple shipped drive
Use Apple Disk Utility to setup RAID(0)
Load files from backup LaCie HD.


03-21-2008, 08:02 PM
You can use Disk Utility Restore function to copy the old drive to the new Seagate. Or you can reinstall fresh, what I would do so I could skip all the language junk and other useless stuff that Apple installs on an OS drive.

I don't get what you are going to set up in a RAID0. You will need a pair of identical drives to make a RAID0. I think you are just going to leave the drives as individual non RAID drives for now.

Watch those LaCie drive. Terrible predilection to fail. Don't count on them. LaCie accepts a high failure rate and just replaces them as their business model. The drives are not good to base a business on since they don't have a high enough reliability. They are fine if you plan on them failing at any moment.


03-22-2008, 07:58 AM
Thanks for the clarification on the RAID and for informing me what to expect using LaCie HD's for backup. There's no point in spending a significantly amount of money on a new system and not have safe, reliable and automatic backup ... I've experienced more than one HD crash in the past. So here are my thoughts ...

Purchase a matching Seagate HD and setup the two HD's as described in "Why and How to Move your Users Directory." That will provide greater speed and easy/safe/reliable internal backup.

What do you recommend for reliable (and hopefully not to expensive) backup for taking off-site? Would it be practical to use the Apple shipped 320GB HD in a Burly enclosure?

Open to suggestions.


03-22-2008, 08:22 AM
One other issue re: my past reply. With the 2 - 750GB Seagate setup as described, what else do I need to do to have a scratch disk for PS3? Can I have a third partition on the Local Seagate to use as the scratch disk? Do I need to purchase another HD for exclusive use as a scratch disk? I could use the 320GB Apple HD, but then what about external backup that can be taken off site. Thanks again for your assistance.

03-22-2008, 09:58 PM
The only time you want a partition for scratch is if the second partition is only for backup or otherwise not used when the scratch partition is being used.

Just use the 320 drive for scratch for now. It will work fine.


03-22-2008, 11:18 PM
That's what I'll do. Thank you for your assistance.

04-11-2008, 12:30 PM
I'm also interested by advice that you can provide.

I have a MacPro 2*2.8Ghz 8-core with 4 Gb RAM

I have two external drives for backup. 500 GB each. The second backup is a backup of the first one (and it's a Lacie. I didn't know their external drivers were not good).

For now, I did a fresh install on a Raptor 160 GB and I formatted the original drive to put my data on it.

I left the Photoshop CS3 scratch disk of on the boot drive because it was faster than the original drive.
But I got an error. Not Enough memory when I worked on a big document - 800 MB. It's weird because I never had this kind of error with my old G4 with only 1.5 GB of RAM. And there were 120 GB free on the boot drive.

I have two other hard drives. A 74 GB Raptor and a WD 250 GB (2 years old).

Is this configuration ok?

1st bay: 160GB Raptor: Leopard (Boot and OSX)
2nd bay: 320GB WD from Apple : Data
3rd bay: 74GB Raptor : Scratch disk for CS3
4th bay: 250 GB (User folder)

... Or should use my drives in another way? Or should I change a drive?

04-11-2008, 01:40 PM
Seems like a good dedication of available resources. Most of your performance gains are coming from separation of all those different file types. Good work - and lots of it to accomplish all the setup tasks you got done there.


06-16-2008, 06:25 PM
Hey Rick,
I had another question on these same lines. I'm currently in the market for a new MacPro system for Photoshop use. I'm looking at one of the Raptor drives for internal scratch disk use, and possibly one for the OS as well. But I was a bit disturbed by something I read on the Apple forums, namely that the Raptor drives don't fit in the MacPro internal HD bays. Can you confirm?

Thanks! I really appreciate your forums. I've gotten a lot of really good info here.

06-16-2008, 07:58 PM
They fit fine, I have 2 of them in my MacPro.

It is the new 2.5 inch drive that won't fit. Those have a 3.5 inch drive size heatsink and they won't line up to fit. No matter since it is silly to buy 2.5 inch drives for the inside of a MacPro, stick with the full size 3.5 inch 150 GB or 75 GB Raptors.