DH67CL Hard Drive Problems

I have a home built computer (serveral) I use all kinds of Intel Motheboards, never a problem until this one. My system has the I7 2600 Processor, 16 Gbs of Ram, a PNY Nvdia GeForce GTX550TI Video card, two Two TB Hard drives, two external Hard drives (Iomega's). I am using the 6.0 Hard drive connectors because both of my hard Drives  Hitachi HDSC30ACA362 and a Seagate ST3200401AS . I have two becuae the Hitachi kept locking up the system, so I thought. I bought the Seagate and kept having the same problem. It would run a few hours, and even though I have power save off, it would be locked up. It did this no matter what hard drive I had as primary. I updated drivers and the BIOS as needed, and nothing helped. I got so frustrated that I went back to my Intl Motherboard DP55WG. I have had no prblems since????

So do I have a bad motherboard or what. I tried everything in my knowledge base and my Borthers, who is IT with a large company in my hometown and also runs a computer busianess on the side. He couldn't figure it out either. Any Ideas would be appreciated because I would like to go back to this motherboard and use all of it's features such as USB 3.0 and the 6.0 transfer rate.

Thanks!!!!