3way 7970 lightning on i7-3820/GA-X79-UD3 or i7-3770k/GB Sniper 3

revro

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which way should i go?
i want multimonitor platform for 120hz gaming. which is better? somehow where i live i7-3770k is 100 eur more expensive alternative.

psu 1200watt akasa, 8gb ram 1600mhz, 3 or 5x benq 120hz xl2420t

thank you
revro
 
first of all what games are you playing on multiple monitors. if its a fps, id say no given it makes a cursor go huge and headshots were extremely difficult

if its a MMO, they arent that demanding in general. if its a racing game, they are not demanding

i7s do zero performance gains over a i5. it can actually be worse than a i5 in some games

2 video cards will be more than enough for your needs.

http://pcpartpicker.com/p/gkhW
 


If you're running 3 way on an i7-3820 your cards will be configured in the PCIe form of 16/16/8, if you are running them on an i7-3770k they will be configured as 8/4/4. The difference is not huge but it will be mildly noticeable. You will also benefit from having four memory channels to serve those PCIe lanes rather than two. If you're getting 3 7970s you might as well get a 3930k over a 3820
 

revro

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well i will be playing skyrim, bf3, crysis 3, far cry 3, gta v, and since i plan possibly 5x1 portrait if 3x1 (6.22Mpixel) is not too big to me :) thats 10Mpixel @ 120Hz so i do need 3 7970 as future proofing or either for 5x1 portrait

i will be aircooling, as i have 2 left hands :) . i will use big tower good case tough only one front fan
http://aphnetworks.com/reviews/in_win_dragon_rider/4
graphic cards are all together in dual slots on motherboards. and this is what i see about temperatures in system with 4 cards without watercooling
http://www.vortez.net/articles_pages/gtx680_quad_sli_vs_hd7970_quad_crossfirex,10.html

thank you
revro
 

revro

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I went through all topics from callsign vega who had 5x1 portrait 1920x1080 120hz setup with quad watercooled 7970 lightning and he and l88bastar have been running @ 150-180+fps on their 10Mpixel setups

according to article above (vortez.net) 3x 7970 amd, not msi lightnings i plan to use, produce in BF3 122fps @ 4,1Mpixel resolution. also i red that from 6.1Mpixel (3lcd) to 10.1Mpixel (5lcd) you dont lose FPS proportionaly to ammount of pixels, so 3x 7970 lightnings shoul suffice.

another fact is that the drivers are getting better and better for 7970

main question is whether the 2 cpus wont bottleneck the 3 cards as i never overclock

thank you
revro
 

revro

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i dont understand, did you mean the 3rd card wasnt much help? have you had cards from different vendors? i mean make sure you buy 3 cards from same vendor and you cant have problem beside heat, though that should be solved by side fan

best
revro
 
yes adding a 3rd card only scales you 50% more performance.

no. if you smack the cards right up against each other, they are going to get really toasty or even overheat if they are open air cooler designs. you will need a very good fan with lots of static pressure to force air between the cards in order to keep them cool
 

revro

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well i recently red that in january 8970 will be released (up to +40% more gpu power) and by april/may when haswell will be out i may just start with 2 cards, and maybe play how temps are if second card is placed just under the first card. if its gpu power is as advertised maybe even 2 of them will be able to feed 5x1 full hd lcds

best
revro
 

revro

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I have experience with your situation. I spent several months trying to make 3 way crossfire worth it. As of a month and a half ago, it was very unstable and, often times, no benefit at all. My system was portrait @ 3860-1920. The same is true for quad SLI @ the moment with 690's though, if they ever get proper per card utilization, that could change. Probably , go with the 3770k or 3570k for PCI-E 3.0 ,so get the Sniper

as i see you are saying that x79 is too much trouble for trifire? well there is this new board coming out apparently much better and in same price range as Sniper, also from gigabyte
http://www.overclock.net/t/1299750/gtd-the-ga-z77x-up7-officially-launched

PS: also the 6gb card would not help much, you would need crossfire or trifire to fully utilize the 6gb with the gpu power of several cards.

so are you already now hitting the 3GB vram limit on you cf/trifire? well i hope that the 8970 will have at least 4gb when they come out in january or february.

thank you
revro
 
trifire is too much trouble for itself

3gb of ram is more than enough to drive a single monitor and good enough for 3. the 6gb card is for when you want to do 6 monitors or 3 1440p monitors but by then you will run into a GPU bottleneck given its not quite powerful enough to use the 6gb of ram effectively