I'm looking on the web for that error and seems related to exhausted ram.
I've 4gb of ram, and game run always at the limit of its; system base + steam uses about 1,5gb of ram, game about 2,3gb, free ram is about 10% while game running, if I try any middle-weight page on the browser when game is open I get a total system freeze because ram going out.
Note that I've disabled swap because I've a ssd as primary disk as.
Possibly also crash is due to exhausted ram? I try to leave open ksysguard to watch ram graphics when game crash, it not seems reach exactly 100% ram at moment of crash.

Buy another 2x2gb of ram identical to my ram cost 43+€ (about 51$), I want to be sure I've at least some benefits before buy it.
My other specs are cpu I5-4670 and gpu nvidia gtx 760. Note that my gpu is on 4x pcie slot because 16x pcie is blown.
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