The specs on my machine i would think is about the minimum for BF3 as i get lag every now and then but it is still playable although not ideal because i got my graphics set on low and 1280x1024 so sometimes i get killed because my graphics didnt load fully at some points when running. I have seen people pop up out of nowhere because of PC lag but i would say 90% of the time its fine and i still land up in the top 10 almost every game i play. (except the first few matches of the day when i need to warm up)
I got a 2.4ghz Core2duo
4gb ram DDR2 667 (yes very underspecced old machine)
geforce 250GTS 512mb ram (Again barely makes minimum with the ram its got)
best shooter game i have EVER played. cant comment on MW3 but BF3 is just the best in my opinion. Played all the other MW games and they were good but nothing like BF3 is.

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