You didn't mention what computer you have.  I can tell you that you can get a least 2 more SATA drives and one or two PATA drives into a XPS 700. You manual should have the information you are looking for.

I have a xps 700
by the looks of it I have plenty of space to add a bunch of drives
I just like to use them for storage and one drive for backing up everything
I sthere a limit to how many drives you can install
I'm not sure what a pata drive is but the drives i have are about 4 years old

Thanks for responding

I believe it stands for Parallel ATA drive. If your drives are hooked up with the old flat cable, then you have PATA drives. There is a flat cable already installed that will allow you to instal two additional PATA drives in the 3 1/2 slots that either could have a floppy drive or a 13in1 media drive, or be empty like mine. Most of the PATA drives will work, but they will run at a slower speed and have less cashe space then a newer SATA drive. Depending on what you already have in your computer, I think you can get up to 2 PATA and 4 SATA harddrives into this monster, but I am not clear on how much total drive space it can handle. The 410 advertises up to 1 TB of HD space, the 700 advertises 1.5 TB, but I saw a dell add a while back that said it could take 2 TBs. With the new 750 GB drives coming onto the market, I would be interested if anybody else could get more then two TBs. I have a lot of home video and pictures that can really hog the space.

Space is rediculous in this "monstrosity" I'm sure i could add 4 drives I wonder what could be the benifit of having 2 sets of sata drives though if you only use it for storage would you really experience the difference in speed when you pull up your files

also any clue why my 2 raptors (160GB each) are so noisy i know they run at 10.000 rpm but they are very loud

I have no experience with the raptors. I would guess it is a speed thing.

When you are trying to work with a video file that is over 30 GBs, speed is everything. Also the bigger the drive, the more necessary it is to access it quickly. A slow drive speed can bottleneck the whole system. It does you no good to have fast graphics and a fast CPU if it is all waiting on the hard drive. It also depends on what you are going to use them for. If you are just warehousing a lot of old pics that you don't use much, speed is not as much of an issue. If you have data and files that you need to access a lot, speed becomes more important.