I have an old g41t ad motherboard and i installed a ddr3-1333 ram on int but when i check the ram frequency on cpu z the mainboard is only using 399 mhz how can i change this?
The older 4th generation chipsets use coarser DRAM multipliers
Since your FSB is set to 1333 MT/s, the FSB clock is 333Mhz.
The DRAM clock that you have right now is 400Mhz, which is the correct clock for DDR3-800. This is generated by multiplying the FSB clock by 5/4.
If you want DDR3-1333 you need to boost this to 667Mhz. You can get this by changing the multiplier from 5:4 to 2:1