Here's what I currently have:

Asus P8P67 motherboard

OCZ Vertex 3 120GB SSD

Western Digital 1TB HD

Windows 7 64 installed in UEFI mode

Even with tools such as Steam Mover, I'm starting to get annoyed at doing so much storage shuffling now that games are getting larger and am looking for a cheap way to increase my SSD capacity. I started reading about Raid 0, and that sounds like the best option to double my capacity and still have one logical primary drive without buying a whole new 240GB+ drive. Here are my two main questions:

1) Will any SATA III 120GB SSD work or do I have to get the same brand or controller (Sandforce.) I ask because the Vertex 3 looks to be discontinued and is super expensive on Newegg now.

2) Trim support was supposedly added for Raid 0 within the last year or so. Is that something I would need to update my BIOS for or would just updating Intel RST drivers be okay for that? That's important because I got this motherboard before the Sandy Bridge recall and therefore have been unable to update my BIOS past a certain version. (I know I should have sent it back at the time, but it was my only computer and there was no indication they would stop supporting BIOS updates for the old revision.)

Any info would be much appreciated.

Edit: After digging around some more, it looks like I would have to modify part of my BIOS. I'd probably be safer just waiting for a deal on a 240GB SSD and selling my old one.

When doing raid, it's best to use the same brand and model of drives.

The idea with doing a raid is building at install team instead of trying to retrofit it later. There is no redundancy in RAID 0 where in fact you have made your file system more fragile where I would only recommend using RAID 0 for temp or swap drive things instead.

It is simple... Do not use raid ever. From experience, I can guarantee that it will cause nothing but headaches for you in the future. Just wait for a deal on a 240GB SSD.

I wouldn't say never. Just like SLI, using a RAID 1 does work well but it is more expensive than many people realize and the performance boost is measurable but not a long term offset.

As for what the OP was doing: You may want to do LVM instead of RAID 0. LVM is what you are really trying to do where RAID 0 is not the right solution for extending drive/volume sizes while LVM is designed specifically for that. I assume Windows has LVM support but I personally never used it on that system.

Go for the bigger drive. Good article on why here: http://www.tomshardware.com/reviews/ssd-raid-benchmark,3485.html

Long story short your sata ports will bottleneck before your raid 0 SSDs do, and larger capacity SSDs generally have better performance than smaller ones.

Yeah looks like even with regular spanning, I'd lose TRIM. What I might do is just keep a look out for a good deal on a 240GB, and then keep the 120 as my system disk. I just wanted to avoid managing 3 drives if I could.

This is probably just me, but if I cared a lot about load times, I would just get a shit ton of RAM and use a RAMDISK instead of dealing with a smaller sized drive all the time. But then again, I am still perfectly happy with my platters.

I agree with you about LVM because RAID 0 is just about increasing speed past the limits of SATA III bandwidth capacities, by mirroring the drives. So the OP would have a faster 128gb drive, not a 256gb drive.

I mentioned never because RAID massivly decreases the reliability of your hard drives for a perfromance boost that would be minimal at best on an SSD. If one drive fails, both drives need to be wiped. RAID 0 increases wear and tear on the SSD and longevity is a major issue with SSD's currently. Then there is the lack of TRIM support, and to answer the OP's question, that is only available on newer chipsets, so unless you bought your drive in the last couple of months then you are out of luck.