OS X on AthlonII X2 445/ HD5750

[Aaleksander]

AMD AthlonII X2 245 2.90GHz
MBD Gigabyte GA-MA74GMT-S2
RAM Kingston 2GB DDR3 1333MHz DualCh
GPU Sapphire Radeon HD5750 512MB DDR5 128-bit 

64GB SSD

 

A few days ago i installed Mavericks 10.9.0 on the upper config. Anything work perfectely, i played COD2, CIV5, SouthPark SOT, Shaun White Snowboarding, using ChemBioDraw and other apps are working well ( games, on full and medium graphic settings ).

 

I know, 2GB are not too much, but i have a question:

I installed The Sims 3 from my origin account, and when I try to play my hackMac restarts... I'm not a gamer ( except Southpark and sometimes sims, for others i just tested ) but I want to know if this issue it's caused by RAM capacity. If yes, i have in plan to upgrade soon to 4GB, if is not caused by RAM capacity,that's means something is wrong in /Extension or .plist... what can I do?

Until saturday i didn't use the desktop for half of a year...And I don't want to invest in it without to know if anything will gone well

 

 

and another Q about RAM upgrade:

Now I have 2gigs DualChannel (2x1GB).. For me it's a bit hard to find 4Gigs DualChannel at a good price* , can I buy one RAM module of 4GB 1333 and it will work?

 

*I live in the darkside of the world, in Romania

 

 

ps. my SMBIOS.plist it's so small:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
	<key>SMbiosversion</key>
	<string>Niresh12495.com</string>
	<key>SMboardproduct</key>
	<string>Mac-F221BEC8</string>
	<key>SMfamily</key>
	<string>MacPro</string>
	<key>SMproductname</key>
	<string>MacPro5,1</string>
	<key>SMserial</key>
	<string>G8031788GWR</string>
</dict>
</plist>

It's possible for some apps to look inside it to know the config?

Thanks a lot!