Thinking to grab Samsung 840 EVO, but the problem is my MOBO only supports 3Gb/s sata.

It obviously will bottleneck the SSD but from my early research, it will only has significant difference for sequential read/write but not so for random read/write.

I'm planning to utilise the SSD for OS (and some programs), which to my understanding usually has pattern of random access with relatively small data transfer sizes.

Opinions would be greatly appreciated.

This is what I want to verify.
Is there any difference running OS using old mobo and the new one? (In terms of boot time, shutdown time, responsiveness, etc.)
Thanks, man.