I was curious. If you have a higher speed RAM(lets say DDR3 1866) and the motherboard supports DDR3 1333, will the 1866 speed RAM still work? Are there any benefits to getting higher speed RAM if it does work besides it being future proof?
The 1866MHz RAM is overclocked to that speed, usually using an XMP profile, or by you entering the BIOS and changing the speed, latencies, and voltage to achieve the 1866MHz. So, if your board's BIOS has the settings you need to achieve the 1866MHz, then yes you can get it.
Is higher speed better? Generally, yes. Latencies affect performance, too. So if your 1866 RAM is 10-10-10-32, it may be "slower" than 1600 MHz RAM at 7-8-7-18.
Future proof? What is that? The current hardware components are light-years ahead of most software and games.................oh, except for Cyrsis!