Mixing Ram and the Variables that Really Matter

[aisarang]

So I had 2x4GB corsair XMS3 DDR3, 1600 MHz, 9-9-9-24, 1.65 V ram sticks that I recently upgraded to 2x8GB crucial DDR3 1600 MHz 9-9-9-24, 1.5V ram sticks.

My question is, can I use the 'old' 2x4GB ram sticks with my crucial sticks without impacting performance? What tools would I use to 'measure' or gauge my performance values? Is this strongly advised against? Etc.

 

[Tradesman1]

It's advised against buying a separate set of sticks with the intent to mix them them as it can be and often is problematic, now that you have them though sure, feel free to try and mix them - could try with the 8GB sticks in slots 1-3 from CPU and the older ones in 2-4 (to keep total DRAM equal in each channel, set freq to 1600, timings to 9-9-9-26, 1.65 and may need to give a little extra voltage to the MC (memory controller), if AMD that's usually the CPU/NB Voltage, w/ Intel could be a variety of things, 1150 is often CPUVTT, early 1155s used VCCIO...to check performance can go to Command Prompt and run Winsat mem or use the free utility MaxxMem, or others