I have a new-ish Z77 motherboard with an mSATA port and decided to get a cheap mSATA 32GB SSD drive (Crucial M4). I plugged it in and it appeared in windows Disk Management utility.
I then read an awful lot about how you need to enable Intel RTS, then RAID, then re-install Windows and rebuild your system etc. etc. !!! I was horrified and thought I had wasted my time as I was not prepared to do all that.
Then I formatted the volume and selected Properties from the right-click menu, and clicked Enable ReadyBoost with the option "Dedicate this device to ReadyBoost."
After re-booting the computer a couple of times the boot time has dropped to just under half what it used to be and the desktop is FULLY responsive within 10 seconds with all the taskbar items up and running.
After booting my favourite Steam games a couple of times each and re-booting there are now no pauses at all for their start-up loading screens, very fast and very nice!
The only downside is that I get periodic pop-up windows complaining that I am "running out of disk space on drive (G:) Cache" as there is only 1% disk space remaining... I would have thought that Microsoft could have sorted this out given the options I have selected!
To relate to your question more directly, if the SSD is connected by a SATA interface I am sure you will notice a very good improvement in boot times and commonly used programs.