8gb Double Channel vs 12gb Ram

[new-gamer]

I have seen many threads but i couldn't find the solution,I am a gamer and i need the exact amount of ram the games eat.Now in some games I have noticed that the ram is going above 7gb and when it reaches 7.6gb something it is stuck there and the need for speed payback for example becomes laggy and stuttering starts.It means that it needs more than 8 gb and in commited section when fully under load in task manager it is also written there about 11gb so i would rather get 8+4gb 1333 ram stick..But should i get 8gb ddr3 1600mhz dual channel or 8+4gb in single channel?

 

[CountMike]

Unknown MB and CPU so I can't tell you exactly but with 2*8GB of 1600MHz there's no fail. In some circumstances with 8+4GB you can also get dual channel but at 4+4 GB with 4GB in single. In any case, having more RAM (if needed) trumps dual channel anyway.

 

[new-gamer]

Unknown MB and CPU so I can't tell you exactly but with 2*8GB of 1600MHz there's no fail. In some circumstances with 8+4GB you can also get dual channel but at 4+4 GB with 4GB in single. In any case, having more RAM (if needed) trumps dual channel anyway.

PC specs:
Gigabyte h61 ds2 dvi motherboard rev 1.0
I5 3570 processor with stock cooler
Zotac GTX 1050 OC 2gb
WD 500GB Green
Mercury 500w Switching Power Supply
Now my motherboard has 2 ram slots ddr3 1333mhz and 800mhz and 2200mhz for Oc,and i want buy 4+4 gb ddr3 1333mhz in dual channel, second option is 8+4 gb 1333mhz single channel,Which should i go for?

 

[CountMike]

If this is the one: https://www.gigabyte.com/Motherboard/GA-H61M-DS2-DVI-rev-10#ov than it should work as I described, 8+4 and should work with 4+4 in dual channel + 4GB in single. That goes for all frequencies.