Getting FIVE times less FPS than I should!

Lastro1

Honorable
Aug 20, 2013
12
0
10,510
The game I really play all the time is Dota 2.

My current setup is:
8GB ddr3 ram
i3-2120 3.3ghz cpu
GTX 560Ti gpu

GPU temperature never goes over 65 degrees, I have maximum no. of fans in my case.
CPU doesn't go over 45 degrees.

I don't even play on 1080p res. My monitor is 900 I believe.

So on minimum settings on Dota 2 with good ping I receive FPS of about 35-40.
When playing on max settings on Dota 2 I receive FPS of no more than 20.

AND when a big team fight kicks off in high settings, my FPS drops to about 5, and it becomes unplayable.

http://www.tomshardware.com/reviews/dota-2-performance-benchmark,3481-8.html
However this benchmark site says I should be getting much higher.

What I have to play in is what they list as "low" detail settings, and I receive about 35 fps, but surely I should be consistently getting over 80?

So confused, have I done something wrong?

The benchmarks on the i3 3220 CPU part at the end is on Highest settings, with the GTX 650Ti,
which I think is about the same or even worse than my GTX 560Ti. Those benchmarks give average 100 FPS opposing to me 20 odd.