no. to be honest, ram does not play that big of an impact in fps. the best way to explain ram is from a programming stand point and apply it to gaming.
say for example i want to record someones position on a map in an x, y and z. i would create 3 variables (names x,y and z) then i would store their position in these variables. the cpu will alocate three 32 bit inteagers in ram, and then set the bits to equal the values i gave it. this has nothing to do with whats being rendered on the screen. instead, that is video memory. with video memory, the gpu's shader units compute the 3d game word and all the textures and how they should be rotated and applied to models. it then says "hey, what is the 2d image this would make?" it computes what each pixle should equal (rgb) and then saves that to video memory. now, lets assume you are gaming on a 1920x1080 screen. thats 2073600 pixles. the way colors work, is you have 8 bits for red, green, and blue (28 bit color depth) with 8 bits for your alpha (which is not used for display, but is used for internal calculations) so lets do a bit o' math... (((2073600*28) / 8) / 1024) / 1024 = 6.921 MB per frame. so each frame needs 7 megabytes of data just to display the image on the screen. now in most game engines you have at least 2 or 3 frames pre rendered ahead of time, so 21 MB of data for display. this is not counting the data that is needed for all the textures and shader data. so why does this matter? well, the larger the screen area, the more data is needed for ALL of that, which is why you need lots of video memory for multi screen setups.
so why exactly do you need lots of system ram? say i load a game, all the non video data is going to be stored in system ram. this includes your health, ammo, kills, the ip addresss of the server your connected to, the buffer for all the network info being sent to and from the game, sound files, the map itsself, ext... so what happens if you have 2 gigs of ram, a gig of opperating system loaded into it, then the game loads a gig and a half of info? well, you cant get rid of the OS. and you need the whole game in ram to run right? so windows will put a gig of game into ram, then shit the other half gig into the paging file. incase you dont know what a paging file is, its a section on the hard drive that is reserved for 'virtual memory'" basicaly windows will put the data that SHOULD have gone into ram there, then swap that to and from ram when needed. well, hdd's are slow so guess what? now you have bad game performance.
in other words, the main performance hit is not having enough ram for games, NOT the ammound if ram dimms you have flled.
now, lets see, if you are doing non gaming (like number crunching on the cpu - which is stupid, now with gpu compute coding libraries) ram does come into play. if you read the post i made, you will know about timings, so doing lots of fetches, lower timing is important, as you are wiating for lots of precharging and waiting. so why does frequency matter??? say you have to wait 9 cycles for a strobe to read (9 cas). at 1333 mhz thats .0067 seconds (6.7 ms). now, lets see what that would be at 1600. after that calculations we find a cas strobe will be a delay of .0056 seconds (5.6 ms). however, low quality ram does not like to run at cas 9 at 1600 mhz. so instead you have to up your timings. usualy 9-9-9-27 ram has to be switched to 10-10-10-30. so at 1600 mhz you will see a cas strobe is .00625 (or 6.25 ms) so you can see that by oc'ing your ram, even though your timings are worse you still get a tiny tiny increase of speed ( .45ms).
so yeah. there you go. thats ram in a nut shell. the difference between 1 or 2 memory controllers is like, nothing. like 1.5% difference (http://www.tomshardware.com/reviews/PARALLEL-PROCESSING,1705-11.html)
so why IS there dual channel ram??? well, there is a bottle neck between cpu's and memory controllers. cpus got faster, and mem controllers could not keep up (due to command rate limitations, and how many qwords are being sent per cycle... blah blah blah) anyway, in short... you add another memory controller, and bam! all of a sudden you removed that small (like rly small) bottle kneck.