I'm in the process of setting up a home server which is basically just an older desktop tower. I've purchased the following items:
Adaptec 3405 RAID controller
4 x Seagate 500GB HDD
I intended (through recommendation of a friend) to setup RAID5, but now I've been told from a guy in the server industry that I should run RAID 10. It is probably worthwhile noting at this point that the drives will store important work files (I'm website developer). I've noticed that RAID controllers that support RAID 10 are far far cheaper e.g. Adaptec 1430SA. Therefore, if I run RAID 10 I am considering returning all my new components and saving money by getting the cheaper card and replacing the HDD's with 4x1TB drives.
I'm confused now at the best way forward and I'm keen to get it right from the outset as I never want to have to worry about losing data anymore.
What would you recommend? Also, why is it so much more expensive to get a card that supports RAID 5?
If you want data protection (aka RAID 5) then keep it. Depending how much you paid for the card (I checked on line and it's ~$350+) you might be well off getting a motherboard (+ CPU) that has RAID 5. For example: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
P45-UD3R $99 after MIR.
The only problem with getting a motherboard RAID is you won't be able to move the RAID array to another PC.
If you make periodical back ups (ie every 1-2 days) then yes, just get RAID 1/0/1+0 card.
Note: RAID 5 is NO EXCUSE NOT TO do backups!
The reason your card is expensive is because of the SAS support and not really the RAID5.