Should i get a new rig? Advice needed

[UVERtainment]

Hi guys, so my main problem that is leading me to consider for a new rig is on Dota 2. Below are my current laptop(almost 3 years old) specs.

Processor:i7-2670QM - 2.2GHz
HDD:750GB
Memory:8GB DDR3
Graphic:Ati Radeon 7690M 2GB
OS:Windows 7 64-Bit

So for a few months, my dota 2 has more fps drops per usual, which leads to uncomfortable enjoyment of the game. Is it because of overheat? My laptop temp is around 70-80 degrees while gaming. I have tilted it so that there is air flow underneath it. Or is it due to my graphics card getting out of shape?

If possible, do give me some advice on this. Otherwise, recommend me a new rig with the following conditions if possible:

My primary game would be dota 2. But i have bought games during the steam summer sale and hope that the rig will be able to support these games (Medium quality gameplay will do)

Example of games are: Bioshock, Dead space, fallout 3, resident evil 6.


Budget: $800

Monitor, KB, mouse are not needed.

Current Considerations
HDD: WD 1TB Blue - $71
OS : Win 7 64-Bit - $110?
Case : Sharkoon BD28 - $73 (BD or T is better?)

Thanks Guys!!

 

[LeroyTanz]

I'm quite the cheap skate, would recommend you to clean off all the dust in the heat sinks. :x Use dust blower or compress air cans. Save up the money.