What's recommanded hardware configuration for transcoding?

Hi! I have a server who run serviio 1.1. It have an AMD Athlon(tm) II X2 250
with 2 gb of ram and 2tb of HDD. It is okay to transcode.But on a couple of video I have an audio/sync problem... I have specified 2 core for transcoding, best video quality and keep original audio. Thanks for your advice.
with 2 gb of ram and 2tb of HDD. It is okay to transcode.But on a couple of video I have an audio/sync problem... I have specified 2 core for transcoding, best video quality and keep original audio. Thanks for your advice.