my question is which brand is best for my rig core i5 - 2320 running on intel dh61wwb3...
Gigabyte is definitely better in terms of reliability and quality but should be a bit more expensive than the HIS. If their is a really big difference in the price, than go with the HIS, else if its a couple dollars more, get the gigabyte
Some may have a slight overclock over the other, but performance wise, they are generally the same