Internet suddenly very slow , latency going high and dropping low in a loop?

[Said]

My internet sometimes goes very slow and then after few minutes it goes to normal, it's like a loop that occurs over and over again . i have tried few things to see if it would affect my internet speed .
i have tried to i cleaned my modem, restarted it several times.
used ipconfig /flushdns in cmd
scanned my whole computer 3times without finding any viruses with Webroot SecureAnywhere
i used ccleaner to clean 10gb's of garbage
i have 3pc's with 2 of them wireless connected, did a speed test on the second wireless connected pc and has pretty much same speed and the one connected with a wire had 30mb/s and latency of 10 the whole time.

here are some screenshots:
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this is when my ping is okey but not the best
http://img543.imageshack.us/img543/5344/5qvz.png

here you can see the clear loop of my latency going up for few minutes and going down to normal
http://img801.imageshack.us/img801/8364/ixby.png

my system
http://img43.imageshack.us/img43/49/rg2q.png

in counter strike global offensive when my ping goes very high for atleast one whole round(5minutes)
http://img547.imageshack.us/img547/2723/9gc5.png

and here it's low again and im owning some people.
http://img838.imageshack.us/img838/2194/76eb.png


i hope i gave enough information and that a kind sir can help me out here, it makes gaming unbearable and watching video's on youtube has pretty much the same problem.
thank you in advance.