Hi, now i have RIG 3x ASUS R9 270x apprx. 44MH/s BUt lots of ppl has 20MH/s for each GPU. I think i make a mistake. I dont know what.

My setup is,
Windows 8.1
Lastest version of etherium
Using Cointron and Dwarfpool.
Lastest GPU driver which is, version 15.20 ( https://www.asus.com/Graphics-Cards/R9270XDC2T2GD5/HelpDesk_Download/)

Any idea why my result is low?