big graphics problems with searing exarch

been slow playing this league, finally got to searing exarch, he's having some weird issues, and its not my connection cuz my connection is fine I checked, and my graphics are good on this computer:

frequently failing to draw to draw some of the effects, particularly the ground effect for his big explosion attack (and boy does it suck to not be able to see attacks that are supposed to be telegraphed because its not drawing the telegraph warning). also failing to draw some of the others at times

also sometimes doing two annihilation of a thousand suns in a row with only enough of a 'pause' in between for you to come back from a portal; and my char is weak, I do'nt have enough dps that they should be doing that rather than their normal.