Well to enable TRIM on your raid 0 SSD you need to upgrade the RAID OROM, which is part of your bios. Unfortunately, the bios asus provides through their website does not included the version of OROM that supports TRIM for RAID 0 with SSD's. You can download a modified bios with the updated OROM from ASUS / ASRock BIOS's with updated RAID OROM. I can personally testify that these bios' are exactly what the creator says they are and nothing more. I have been using the modified bios' from this link since the beginning of November and I have not once encountered a problem and I have had all of my questions responded to and answered. You will need to flash the bios via the USB Bios Flash Back function, this is where you put your bios image on a usb drive, rename the bios file to the correct filename for your motherboard (the correct file name is "M5F.CAP" without the "" The complete instructions for using USB Flashback can be found in your motherboard manual chapter 2 page 19, it appears at the bottom of the page as 2-19, link to pdf manual at bottom) connect the usb drive with the renamed modded bios file to the usb bios flashback port on the back of your computer, press the usb bios flashback button and wait for the light to start flashing then stop flashing and go out completely, after that is finished your new bios is installed. You will need to reconfigure your bios settings. It is also EXTREMELY IMPORTANT that you delete your current raid array and recreate it and then do a fresh install of windows 7, if you do not do this TRIM will not be enabled, and you might have issues installing the latest version of the Intel RST Driver. From my personal experience I was unable to get Windows to finish booting after I tried installing the Intel RST 18.104.22.1683 driver while using the array I setup with the old OROM that comes from Asus, I was able to use the RST 11.6.x.xxxx version with no issues but I was not taking advantage of TRIM nor was I getting the best possible performance I could have got, after recreating the array and reinstalling Windows 7 with the Intel RST 22.214.171.1243 I have experienced no problems of any sort. You will also want to download the latest drivers from the asus website, with the exception being the Intel Rapid Storage Technology Driver, since you have an updated OROM you want the most up to do Intel RST driver which is currently 126.96.36.1993. You can find the download to that driver here - I can not post more then 2 hyper links, the driver download is in the link at the top " ASUS / ASRock BIOS's with updated RAID OROM" on that page it is at the bottom of the very first post after the bios' listed - you will want to download File name: iata_enu.exe. There are descriptions of what each download is for in the "Detailed Description" portion of the driver download page.
You might want to follow the instructions on this post if you have been using your SSD's in a raid 0 config without TRIM being enabled. - HOW TO GET YOUR SSD PERFORMANCE BACK you will want to pay attention to the part about "secure-erase" the entire process to secure-erase takes only a few seconds per SSD. I did the secure-erase after I deleted my array and before I recreated it, this was because I had been running a raid 0 setup without TRIM being enabled for about 6 months and I wanted to have a fresh start when I recreated the array with TRIM support and the new RST OROM/drivers.
I would suggest having all your drivers downloaded to a usb drive or something else before you delete your array and format your hard drives. This will make everything faster/easier once you have the OS re-installed, also you never know if you will need to install the LAN driver to get access to the internet.
Installing Windows 7 from a USB drive is considerably faster then installing it via dvd, I was able to see my desktop from the start of the installation in around 15 minutes.
Your motherboard manual can be found on the asus download page, enter your motherboard model and then select your OS, go down to the bottom of the list and click "Manual" and then find "MAXIMUS V FORMULA/ThunderFX User's Manual (English)" on page 2-19 you will find the instructions for USB Bios Flashback
I hope this has helped, I will say that once you get the SSD raid 0 array setup with TRIM, the computer is smoking fast. Benchmarks consistently break 1000+ MB/s read and write!
Apparently I can not post images as well since I am a new user.