Before we even look at the data, I need to be clear about this: This is a temporary storage solution. I just built a new computer, but I plan on buying an SSD in about 6 months, or whenever some more SATA 6.0 Gb/s drives come out. But, right now I need a boot drive. (I have a separate storage HDD.)
Since this is temporary, I just want to use some old hard drives. I have installed windows on each and tried running some tests. I have tried a single disc which is a Barracuda 7200.10 500GB, SATA 3.0 Gb/s, and a RAID 0 Array with 4 WD Caviar 7200 80GB discs. The WD's are older, and are only SATA 1.5 Gb/s.
This picture shows what HD Tune gave me on read speeds, but I don't really know what to think. The single disc looks pretty terrible, but the RAID array has longer seek times. I haven't timed windows boot times or anything more practical, but I sure haven't really noticed a difference in the couple of days I've been trying both. So, being a 6 month solution, which should I keep? Are seek times or read speeds more important for practicality?
RAID only improves transfer rates, not seek times, and so with those older 80GB drives it's easy to see why the seek performance is so bad.
For most general-purpose use seek times tend to be more important than access times, so my proclivity would be to use the newer drive for the OS disk. You might want to partition it down to the size of the SSD you expect to buy as a sanity check that the size is appropriate for what you want (it'll also keep the transfer rates and access times in the optimum range).
The exception to that might be if you have to copy or read fairly large files with the programs you typically use (music and video playback excepted).
6GBit/SATA SSDs aren't going to be any better than the current 3GBit drives unless the actual controller and/or flash chips are themselves faster. The SATA connection isn't really the bottleneck for most drives.
You might want to partition it down to the size of the SSD you expect to buy as a sanity check that the size is appropriate for what you want (it'll also keep the transfer rates and access times in the optimum range).
Will there actually have a performance increase with the partitioning? I don't plan on storing anything on this drive - just windows, apps and games. I don't expect to ever use more than 80gb at any given time.
The barracuda isn't exactly new either. Those huge dips in read speed didn't appear to be a fluke - I wasn't running anything else while the test was running, and I tried it a few times. What are those dips from and is it a big deal? It sure doesn't make me feel any better about the single drive.
So it sounds like the access times aren't that important, will I notice a difference with the extra 30-40 MB/s on the RAID?
This is just a system drive - I will only be using about the first 80 GB, so it will always be around 70 MB/s if I use the single drive.
Partitioning will give you a slight performance improvement, but it's questionable as to whether you'll actually notice it. My main reason for suggesting it is that if you plan to migrate to an SSD later on then partitioning is a good way to see if, say, 80GB is something you can really live with.
My experience is that fast access times tend to be more important than fast transfer rates in making the system feel responsive. But it depends pretty heavily on the kind of work you do. If you spend a lot of time copying large files or use programs that need to read or write such files quickly (photo or video editors, for example) then you may be better off with high transfer rates.
I don't think I'll be copying large files, and if I was, it would be using my storage drive. I plan on just re-installing windows when I get an SSD - I've never been a fan of migrating, and since I keep my storage separate it isn't a big deal to do reinstalls or swap hard drives.
I'll probably stick with the simpler setup with just the one drive, and I'll try partitioning it down to see if it makes a difference for performance. Thanks a lot for the advice!
Not sure if you're too interested haha, but I tried short stroking the 80gb drives to 25gb each and RAID 0 again, and I'm now at around 120MB/s read and 13ms access times. I think I'm keeping this setup!