imac HUGE problem here.

hey macrumors users, need determine problem 2011 27" imac has. i've been reading everyones issues months, , happy mine had none of them, now, mine has big big problem (i think) , never seen before on forums.

started 2 days ago (bought 9 months ago on august 4th 2011). , became worse when started. started kind of snow in display.. it's hard explain , flickering. now, it's ****ed up. started when using lot of windows @ once, , didn't did before.. maybe broblem didn't happen before because wasn't using compter's multitasking capabilities, do, it's ****ed up..? don't think heat issue cause use smcfancontrol speed fans bit, , monitor temps istat nano , know fans work properly.

when use computer , problem appears, can still use computer until display goes black , works no more. have shut down computer , wait 5 minutes fore display works again..

when use computer notice it's alot slower when problem started , problem doesn't show if things browsing in safari, itunes, etc. when play games multiples windows, bam, here again. oh , when problem appears if put computer sleep , wake up, problem gone , doesn't show while..

edit: , it's not display computer freezes when play games , need shut down power button.

guess gpu or motherbord.

posted 2 videos of problem on youtube :
http://www.youtube.com/watch?v=-ohsj0-xsvm
http://www.youtube.com/watch?v=myzmgewirrs&feature=youtu.be


here specs of machine:

intel core i5 3.1ghz
12gb ddr3 ram
amd radeon hd 6970m 1gb
1tb hard drive
running on mac os x lion 10.7.4 (11e53)

guys think problem , how repair cost?
thank reading , appreciated

 

have taken in apple store yet , have them @ it? rather post youtube videos think want professional @ problem.

 

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