You have bought an excellent card. I thought they were great at 140 bucks from Dell, used. Adaptec can be spotty, but I have had NO problems with the 29160N.
The major objection to scsi is usually price, but you seemed to have dodged that bullet.
I'd go for the drives, and see if you like it. Good cables can be expensive, too.
I've found that cheetahs work very well for desktop systems. According to Eugene, that must mean the algorithims and firmware are setup well for desktop use.
Your major advantage with scsi is the components are higher quality, designed to last longer. I like to use coolers on my drives, as added insurance.
I do use a couple Quantum LM's in other machines everyday. They work well.
If you aren't happy with the speed, you can always buy one of the 3 current super fast drives, and have the fastest drive around, by quite a bit, and use the other two for storage.
Actually, if it was me, seeing as you have already bought the controller, I'd go for the fastest drive avaliable. I think they are 250 or so from hypermicro. If you want speed, that's the way to go.
A long time ago, I installed an old, POS IBM drive in a desktop, scsi, and started a real flame war. It only moved at about 16 mb/sec, but it was still relatively snappy compared to the ide drives I had at the time.
Perhaps scsi drives, with firmware optimized for servers(many random reads?)
work well for desktops, that tend to do the same sort of work?
I also wonder about this statement:
Finally, your system is a major component in speed. As your computer chip
gets faster, and you have more ram, the speed affect of the hard drives
diminishes. In other words, the faster the system, the less noticeable the effect of changing hard drives becomes.
The most ram I've worked with is 512, and I've got that in two of the machines I work on, and 384 in the other, that's with Windows 2000. I'd like to try a gig of ram, but, I think, given the ram pricing, I'd be better off moving up to a Xeon system, with a gig, or more of ram. Maybe later.
By the way, the reason I buy scsi drives is reliability AND speed. I've still got the first generation cheetahs I bought, and I use them for backup, in an external raid box. They are pushing 7 years old.
I figure the time I've saved in not having drives fail, and reinstalling, is worth the extra cost.
Don't do this half ass. Get the fastest drive on the market, or the Cheetah 15.3,
and see what all the fuss is about.
I've rarely found anyone that is disappointed by Cheetah's as far as speed goes.
And, if you are, then you can buy another cheetah, and a raid card....