Clear CMOS when adding RAM?

[Typefighter01]

If I am just adding 2 more sticks of the exact same ram I already have installed, do I need to clear the CMOS? It is an ASUS M4A89TD PRO USB 3, it currently has 2 sticks of Corsair CMX2G3M1A1600C9 (4GB total) and I would like to add 2 more sticks (8GB total). I don't feel like fooling around in the BIOS if I don't have to, but I have a feeling the MOBO won't "see" the other two sticks unless I clear the CMOS. This computer currently resides in my virtual pinball machine and I am doing a few upgrades. I am running the 64bit version of Win 7, so I know it will use all 8GB...Thanks for any help

[DHTech]

no you don't need to clear the cmos, your mobo should automatically see the new ram, if not you will need to update the bios settings.

[JDFan]

Should be plug and play - meaning you put them in and they work, that said depending on what speed rating and voltage the modules are and what MOBO you have it may or may not boot the first time -- Some MOBOs have slight voltage droop when filling all 4 available ram modules on the MOBO which can cause the ram to be unstable at the specified voltage\speed ratings if the modules are also very close to their upper rating limits - so it may not boot properly once you put the new modules in and then will revert to more conservative settings on the next boot so that it can boot.

If this happens you may need to go into the Bios and tweak either the voltage (increase by one step maybe 2 to help counteract the vdroop) or loosen the timings on the modules so they are stable under a slightly lower voltage. Thus it may take some adjusting depending on the system to get the best stable performance but in answer to your initial question No it should not need a CMOS reset.

[Typefighter01]

Thanks for the quick respone guys...I know the DDR3 1600 I am using is not considered overclocked RAM on this board and (IIRC) unlike the dedicated CNC computer I am building I didn't need to set the RAM frequency in the BIOS when I first built it, I believe it did it automatically. I guess ultimately I will know the answer when I pop them in, I was just worried I would have to go through the BIOS settings again (I am running an SSD, so I had to change a few settings when I first set it up and I don't remember exactly what I did, something about enabling AHCI  ).