I just started mining, my rig has two rx 290x's but my cpu is a crappy ole Pentium. The issue is when I try to mine any coin on MultiMiner or Minergate I get about 600 h/s total when 60mh/s is what I've been told I will usually receive. when I boot task manager it shows my CPU is at 100% load constantly from running these but the gpus are chilling at a cozy 4%. Why is this ?