First - For add on SATA III card. Card probably based on Marvel chipset, so Intel driver can not be used, you would use the default USoft AHCI driver. Would still use the Intel RST for your SATA II ports.
For Sata II, If that "Intel(R) driver was listed in device manage inder the IDE ATA/ATAPI Controller and msachi is NOT listed then you are good.
So if I use the default USoft AHCI driver will it support TRIM?
Also what do you mean by default?
And thanks for your time your are a good person to help us!