Windows 8 high memory usage

Dinfiniti

Reputable
Jul 26, 2014
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4,520
my specs
msi ge 60
core i7 4700MQ, gtx 765M ,8 gb DDR3, windows 8 64 bit
at start up itself memory usage is over 55%
while using firefox it is over 60% at around 5 gb but if add the memory consumed by processes in task manager it is around 1.5-2 gb
a week back it was around 23%
avast free could not find anything even rkill and malwarebytes were ineffective
there is also 100% disk usage while using utorrent
any help would be appreciated thank you