Computers - Second Hard Drive

With my desktop I want to add a second hard drive that is ONLY used for backup of picture/videos and the like. I need a stable way to store my info (I despise external hard drives because of their failure rate)

Anyways, my desktop has room on the motherboard for two SATA spots I believe. Those two are used for the DVD drive and my hard drive. I am wondering the best way to go about this. I know there are some splitters out there and I have heard mixed reviews regarding them. Any suggestions? Does anyone use a splitter? Any ideas that do not involve an external drive?

Assuming you buy quality ones which are properly cooled (fan tends to be best) they should be fine. (Segate under 1tb or western digital).

Alternatively see if your mobo has an ide slot. - Be a little slower, but not noticeably so, and should work very well. (+ Cheao drives)

If your pictures are irreplaceable (and they usually are), consider a thumb drive (or an on line storage utility like Gmail, Carbonite) kept in some other part of the house. What if your computer takes a hit from lightening? Or that room catched fire. By adding a hard drive, which is a good idea, and storing all your pictures, music and documents on it, you are putting all your eggs in one basket.
Having said that, an additional drive is a great idea. There are PCI SATA expansion cards but first make sure there are no PATA ports (there almost certainly is) or other SATA ports. If you go with the PATA option, you might have to go into the BIOS to change the boot order.