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View Full Version : 640GB RAID0 vs 300gb Velociraptor




sboerup
Mar 9, 2009, 09:59 AM
I've done a lot of research a while back about the 640gb 6400aaks (blue line, black is a smudgen faster) and the 300gb Veloci.

I first purchased a Velociraptor back when it was $300 and didn't think it was worth it and was happy with the 640gb. That was before I got my Mac Pro and realized it's worth spending some money (and back when I didn't have a lot of extra spending cash). I might have answered the questions myself, but I had to see if any other users have tried this:

I recently did a RAID0 of (2) 6400aaks drives, and currently getting 210mb/s+ on both read and write. Now, this is my boot+apps drive only. Honestly, I really couldn't tell a difference from my previous setup as a single 6400aaks drive as boot.

Since the RAID0 is taking up 2 HD slots I wouldn't mind freeing up a slot if the 300gb Velociraptor will be as fast or faster. I know it maxes out around 115mb/s, but the seek time is going to be much better. Considering I don't need hugely fast read/write times, will I notice a difference or will it be negligible?



twig16
Mar 9, 2009, 10:45 AM
in absolute terms:

AAKS X 2 in RAID 0 is faster
than the Velociraptor which is faster
than the AAKS alone

But, since you couldn't tell the difference between the RAID 0 pair and the single AAKS to begin with, can't you tell here that the Velociraptor is not worth your time and money for this application?

I know you are drawing a distinction between read/write and seek, so it is not a totally empty question.... but really....

vicentk
Mar 9, 2009, 11:21 AM
I had been try 6400AAKS and 6401AALS, both speed is nearly.

Left is 4*6400AAKS in OSX software raid0
Right is 4*6401AALS is same setting

After I use few months, AAKS is not better in IO, AALS is better in IO. As you can see AALS had dual IO so it make more stable.

Nik
Mar 9, 2009, 11:23 AM
The point is that the speed of the Raid0 does not decline as fast as it does on the raptor drive.
I will configure my new mac pro with not two but three 640GB Western Digital Caviar Blue drives plus a 2TB TimeMachine Drive.

I will partition the four drives as follows:

3x640GB Raid 0: 1787GB formatted space:
Scratch for Photoshop: 87 GB
Macintosh HD: 1700 GB

1x2TB: 1865GB formatted space:
Windows: 115 GB
Movies & TV Shows: 250 GB
Time Machine: 1500 GB

The Time Machine is smaller than the Macintosh HD. Since I will not use all the 1.7 Terabyte it does not matter.
As soon as I hit the wall I will outsource the Movies & TV Shows and get 250gigs of extra space.

Horst
Mar 9, 2009, 11:42 AM
3x640GB Raid 0: 1787GB formatted space:
Scratch for Photoshop: 87 GB
Macintosh HD: 1700 GB


To the best of my knowledge, the whole point of a Scratch disk is that it's on a dedicated HDD, not on a partition of the same physical drive/Raid array as the system/apps drive.

As for the OP, I played around with 2x WD Black 640GB in Raid0 vs. a Velociraptor as boot drive.

The VR is slower, but keep in mind that there isn't much Read/Write going on on your system drive, if you keep your data elsewhere, and program/OS boot times are not of any importance re. performance .

So now I use the faster Raid0 for a Scratch partition and a 2nd partition for big files I'm working with, the VR as system/app drive.

Storage and backups are on external FW drives.