well, your CPU is good enough for gaming. so no need to upgrade. though a little OC will yield better performance..
your PSU is good enough. and it has 4*6 pin and 1*8 pin and it also has a high wattage so no problem if CF/SLI. so all you need to upgrade is the cards. so all you need to upgrade your gfx and ram.
you can get a nice R9-290, it performs like GTX 780 but cheaper. and if equipped with a good cooler your seeing performance as good as a single GTX titan.( though rumors are no aftermarket cooling till january) .
and another 4GB should be good( though 4GB is still good for now)
Thankyou thasan1 for response. With SLI ( i guess this is running 2 cards together) will it be okay to run 2 different cards? I know when PCI-e was first around it was better to run 2 of the same cards..
Also my cpu is running fairly hot as it seam about 70 degrees up to 80degrees and sometimes even high so this will probably be my issue with the pc just turning off. WIll this have damaged the CPU at all?,,
I am going to buy some more paste and see if that cools it down.
instead of buying new paste get a new cooler. a CM hyper 212 evo is a great one for 30 USD (idk about AUD but it should be cheap) you should be able to reach 4Ghz+ with that cooler with temps under 75-80C. and as for SLI no you can not run 2 diff cards. they need to be exact same model (i.e GTX 660 with GTX 660 or HD 7950 with 7950)