I am going to be getting a RAID motherboard and was wondering if I could do this:

Right now I have a 13GB WD 5400RPM drive. Can I buy 1 more 13GB drive that is 7200RPM and run them together?

Or do the drives have to be exactly the same?

If not, would I be better saving the money and just buying one more 5400RPM 13GB drive, or is 7200 the way to go?

Yeah, you can do it, but it's not adviseable to run drives with different rpms, since you won't get nearly as good of performance as with 2 7200rpm drives. If I were u, I'd just buy a couple new drives instead of tracking down a mate for your 13 gig. I mean, 20 gig 5400rpm drives are less than $90 at best buy, and you can get 30 gigs for a little over $100. Probably find 'em cheaper online.

How much more performance will I get out of 2 7200RPM drives vs 2 5400RPM drives?

Well...I dont have alot of RAID exp with 5400 rpm drives, but I have 2 maxtor 30 gig 7200 rpm drives with a promise fastrak 100 card.
Using 2 7200 rpms, I get an average of 52 MBps.
Very quick.

Getting 2 20 gigs would be advisable, cause those new 20 gig platters are nice, but, going with a 5400 rpm, will cut down your speed and your seek time, when using raid, whatever the seek time of your hard drive is, you can almost multiply that by two. My seek time is close to 14 mS, which isnt that horrible, but the seek time will go up with 5400 rpm drives.

Brain would know more than I do about the 5400 rpm raid config. Maybe if he posts his average throughput you can compare between the two. I used HDTach for the benchmarks.

Hehe. I wish I had RAID right now. I'm just going by what I've read, and spouting it out.
Oh, and I'm just guessing that you'll be doing RAID 0--striping. It will increase performance, but just realize that if one drive bites the dust you are not going to have a good day if you didn't backup your stuff.(duh)
From what I've been told, mixing speeds doesn't cause any data problems, but it doesn't do the faster drive justice.
Basically, it comes down to how much you wanna spend on drives.

I figured u had raid goin

O well...
I agree with brain on the price part.

It all comes down to the price...

Nope. I'm actually glad, seeing as I'd lose 5 gigs in the process. I also don't like the way the Promise IDE RAID bios doesn't allow you to not RAID anything. The HPT370 on my VP6 does, which is very nice.
This is only in on-board IDE RAID, BTW. The only IDE card I've seen used is a promise ATA100 non-RAID, and it works the same as the one on my A7V.

Ok... For a motherboard I was looking at the Abit KT7A-RAID, or the EPOX 8KTA3+.

Does anyone have any experience with the Epox? I have had Abit's and been happy with them. Not sure if I should look at the Epox.

Also, if anyone else has any other motherboard suggestions it would be appreciated. Only thing is, it has to support SDRAM. I have a lot of SDRAM and don't want to have to buy DDR right now.

TIA