There's a mysterious card in my computer, and I need to know whether it's critical to the system or not. So I turn to the PC literate to help figure out if I need to keep this. I'm building a custom PC and the number of PCI slots affects motherboard cost.

The card is labelled as a FastTrak TX4200. Doing a little googling comes up with this page:
http://www.promise.com/product/product_detail_eng.asp?segment=RAID%20HBAs&product_id=127

"Cost-effective Enhanced SATA RAID 0/1/10 PCI Adapter
The Promise FastTrak TX4200 4-port SATA RAID PCI adapter offers a low-cost solution for implementing a RAID 0, RAID 1 or RAID 10 storage system with up to four high performance Serial ATA disk drives. Promise Technology is the leading provider of Serial ATA interface solutions, and with the FastTrak TX4200, users can benefit from Promise's experience in maximizing Serial ATA storage system performance."

I only have one hard drive that I use (http://www.amazon.com/Seagate-Barracuda-Refurbished-ST3400832AS-7200RPM/dp/B000P4XEC2) so I don't know why this is in there.  Could anyone help me understand if I need to move this to my new PC, or if I can save cost by getting one less PCI slot? Thanks!

If your using only one HDD, then no, you don't need it. I'm curious to why anyone would need it actually, most modern motherboards are capable of several disk RAID set-ups themselves. 

If your hard drive isnt hooked up to it then take it out and put it aside (you could also just dispose of it if you want but you did pay for it). If your hard disk isnt detected then put it back in but chances are its just there because its aimed at people who want to do hardware RAID.

" @Pazy said:

" If your hard drive isnt hooked up to it then take it out and put it aside (you could also just dispose of it if you want but you did pay for it). If your hard disk isnt detected then put it back in but chances are its just there because its aimed at people who want to do hardware RAID. "

It's probably sofware RAID anyway, it's a cheap-ass controller. "

it sounds like it's useless. modern motherboards have slots that could use SATA cables from the motherboard. so take it out and see what happens.

Since you don't even know what RAID is, I'm going to go out on a limb and say that it won't matter if you got rid of it. If you have a hdd(s) connected to it then you probably shouldn't mess with it unless you know where to plug in an IDE or SATA cable into your motherboard.