Need help with Raid!!!

[JamieLee2k]

Ok later on today I am going to get my new HDD a maxtor 250GB SATA in which it gives me loads of space since I will then have 4 HDD's installed and then I can set up raid, I heard how it is so good and makes your computer run faster but I don't even know anything about it.

Come someone explain in simple terms excually what it is used for and why I should use it?

 

[JamieLee2k]

Here are the HDD's I have or will have in 1 hour
250gb SATA (Not sure of model yet) - 7200RPM
120gb SATA Seagate Barracuda - 7200rpm
120gb IDE Seagate Barracuda - 7200RPM
40gb IDE Western Digital Protégé - 5400RPM

Now I wouldn't even know what to do or even how to use Raid.

So far I have:
120gb SATA Seagate Barracuda - 7200rpm as my master with my OS on there
120gb IDE Seagate Barracuda - 7200RPM - Backup drive
40gb IDE Western Digital Protégé - 5400RPM - Backup Drive

 

[JamieLee2k]

Just to add to that above I have a ASUS A8N Deluxe motherboard and a AMD X2 Duel Core 3800+ also.

 

[JamieLee2k]

I have just brought a 250gb from my m8 so I can't afford to buy another 120gb SATA drive unless someone wants to swap my IDE for a SATA, not gonna happen though