4 gb ddr3 1333mhz(old) + 4 gb ddr3 1600 mhz(bought) Dual or single channel

[Thanoj]

I have 4 gb ddr3 1333mhz installed before a year. Now I had bought 1600 MHz 4 gb ddr3 ram.
My PC specs:
Asus M5a78lm/usb3
Amd fx 6300
gt 730
4 Gb ddr3 ram(now installed) another 4 gb ram yet to install in my mobo.
Will it make any difference on gaming,will my mobo be using 1600mhz or 1333mhz
I have a doubt , will my 4gb ddr31600 MHz+1333mhz will it be acting as a 8gb 1333 MHz with auto setting in bios.

 

[Darkbreeze]

If all the installed memory is 1600mhz, then it should be 1600mhz. If the 1333mhz modules are also installed, then the 1600mhz modules will default to 1333mhz, if they even run together, which is not guaranteed by any means. Also, if you add more 1600mhz memory, I'd make sure it's the exact same part number as the 1600mhz modules you already have installed if you want there to be much chance of achieving dual channel operation. Even then, if all the installed modules were not purchased together in a matched set, there is not only no guarantee they will run in dual channel, they might not even play nice together at all.

As far as your performance is concerned, having 8GB instead of 4GB certainly can't hurt, but I wouldn't expect to see any dramatic changes in performance. The best way to know if you're going to see any benefit from adding additional RAM is to open resource monitor and see what percentage of memory is being used when the system is under the conditions you normally are gaming at. If there is still a considerable amount of unused or reserved but not in in use memory, then you probably won't see much if any difference. If you are at about 75% or more of available/installed memory being in use, then you might see some benefit.

I certainly would prefer to see 8GB of 1600mhz memory installed than 4GB of 1333mhz memory installed, in any given situation. You may need to manually set the memory to 1600mhz in the bios, as the default maximum SPD is 1333mhz.