RAID 0 should get you faster reads and writes, but you do you really need that? Note that if you lose one drive of a RAID 0 pair, you just lost the volume, where with with two drives operating independently, you've still got the data on the good drive.
Also, note that without special driver support, you'll be giving up TRIM support on the array.
I think RAID implies AHCI, on Intel boards at least.
You need to read the question properly.
He is asking about RAID0 STRIPE, not RAID1 MIRROR.
My answer: YES you will have a significant speed improvement.
ref: http://staff.science.uva.nl/~delaat/rp/2009-2010/p30/presentation.pdf
Speed:
My workstations do run Linux Mint using software raid (mdadm)
and I do run 4 drives in a stripe having XFS as filesystem.
Once you sit on such workstation, You do not want to turn back
to the old days with ONE platter drive.
Backup your workstation daily with incremental backup, weekly
a full backup just in case one SSD crashes.
Your speed is great but if ONE ssd does crash You loose a lot of data.
So You are warned.
Backup and use cloud to store additionally files.
Storage:
My NAS is purely running FreeBSD ZFS ZRAID2 for storage
with 2+4 drives of 3TB, so I have 12TB and 2 drives of 3TB do provide
redundancy, so I can loose 2 drives at a time without loosing data.
My NAS does run on regular drives.
ZFS is currently the best filesystem for disks, for sure for storage.
You can look for FreeBSD or a dedicated NAS software solution such as FreeNAS,
ZFSguru, NexentaStor ... I did choose ZFSguru because I do like to teweak
the FreeBSD system. I use iSCSI and SMB/NFS shares on it.
Servers:
My favorite is to use platters for ZFS and use SSD for ZIL in ZFS.
But it is dark art.
NOTE 1:
Try to avoid hardware raids, in case of failure You need to have the same
hardware again. Do not use the cheap raid controllers on the customer
motherboards. Try to use software raid supported by the OS, just for sake of
recovery, as the OS has more ways to deal with raid as most crappy raid software
in those hardware controllers.
NOTE 2:
When using ZFS avoid at all costs hardware raid controllers. Look for
motherboards with enough SATA ports to connect Your drives. There are
dedicated controllers to without raid functionality.
Setup the raid using ZFS
NOTE 3:
SSDs no longer scale after 4 disks
HDDs continue to scale after 5 disks
NOTE 4:
There are different types of SSD
You have SSD SLC and MLC. The first are the most expensive but
the fastest and the best for heavy read/write operations.
Best Answer
I would definitely get the single, larger drive. It's unlikely that RAID-ing two smaller drives will provide a useful performance increase, and the TRIM command (which helps preserve an SSD's performance over time) probably won't work.
The SSD's controller should also use any free space to help maintain performance and maximise the life of the drive (by minimising the write amplification ratio). With two smaller drives you start out with a lower potential to take advantage of this.