Well the OC is Overclock meaning the processors at stock (that are supported by the board) will support 1066 but if you overclock then you could get that up to 1333. The one that supports 1333 and does not state OC most likely means the same thing but if not it would mean that the memmory controller can handle 1333 as a stock setting.
Thank you Thent for replying,
does it mean, mobo (msi G41M-P26) will support
1. 1066 MHz (rated) RAM Overclocked to 1333 MHz, also
2. RAM rated 1333 MHz (in both slots)?????
3. is it ok to opt for 1333 MHz rated RAM???? (These are cheap and easily available)
cpu: pentium d 820 (800FSB)
mobo: msi G41M-P26 mobo (box says it supports 800,1066 MHz RAM, official site says OC 1333 MHz, 1066, 800 MHz RAM)