To spare folks the pain I went through, the following does not work:
Adaptec 5445 (or 5 series Raid card) using firmware 16116 and 16120 drivers, with 2x Mtron 7500 (firmware 0.18R1H3) does not work. I tried to use the Adaptec 5445 as a RAID card for a RAID 0 array and after 2 weeks of working with Adaptec, Adaptec admitted that it doesnt work, that Adaptec has purchased Mtron 7500 drives to make a new driver/firmware, but in the end.....that:
-->> Mtron is NOT listed on the 'compatability guide' <<-- for Adaptec 5 Series controllers. Gee thanks.
What does this mean?
If you read Toms Hardware often like I do, and decide to take the 'best' RAID card (listed as a 5 series Adaptec card), and pair it up with nearly the best SSD (Mtron 7500's....., MemoRIGHTs are too expensive) beware for a headache unless there are new drivers. The system was unstable and would 'pause' and eventually lock up after not more than 90 min.
If you want a high end system, and want to user Mtron SSD drives (or any high end SSD drive) and avoid the slow RAID performance from the Intel ICH8R/ICH9R chipset on a motherboard....dont go to Adaptec for help. They are 'working' on it. I thought of Adaptec as a leader for a long time in RAID controllers, but this whole experience really has put a bad taste in my mouth (and wallet).
I ended up getting an Areca 1231ML and it worked out of the box w/o issue....plus it comes with 1gb ram (double Adaptec's), and came with 3x the cables and drive capacity.
On high end systems, RAID cards provide little performance benefits for RAID0 with 4 drives or less. On the other hand, several RAID cards work with VMware, Linux, etc. For me, that's a compelling reason to buy them, particularly if they don't cost as much as the rest of the system.
If you want top end performance, go for a RAID card. While onboard RAID does work, its not as fast as a dedicated card.
Not really true for RAID 0. Intel's integrated RAID 0 is actually quite fast, and if you enable some of its caching features, it can use a little bit of system ram to allow for significant performance gains. As I said, nothing beats a dedicated card for RAID 5 or 6, but for just a simple, 2 disk RAID 0, I'd be surprised if there was even a measurable performance gain.
Comparing IOP341 dedicated raid cards (highpoint 3520, areca 1231 ...) to ICH10R using pcmark05 with 6xmobi in raid 0 - the dedicated raid cards are faster than ich10r by approx 2000 pcmark05 points even though hdtach sequential read/write looks to be the same (ich10r vs iop341). Ich10r is very good but dedicated pcei cards are better.