RAID 10 crashing

[DeepFrz97]

I built this computer about a year ago and it works great with one exception. If I leave the computer on overnight one of the four drives in my RAID 10 array will become unstable and crash. If I mark it as normal in the ASUS RAID setup and rebuild it everything works fine until I leave the computer on overnight again. If I turn it off after I am done using it everything goes fine and I have never had a crash. Also, if I leave it on for an extended time more than one of the drives will fail and this has caused me twice to have to recover windows. I am thinking of either getting a different motherboard or a RAID card. I would prefer not to if it is something that could be fixed otherwise.
The computer is not used for gaming, but rather photo and website editing.
Here are the specs:
1 - NEC MultiSync PA241W-BK-SV (Not included in Price)
1 - Viewsonic VX2439wm 24" Widescreen LCD Monitor
1 - Cooler Master HAF-932
1 - Intel Core i7 875k
1 - ASUS P7P55D-E LX LGA 1156 P55 ATX Intel Motherboard
1 - Seasonic USA X-Series SS760KMACTPFCF3 760 Watt PSU
2 - Corsair XMS3 8GB DDR3-1600 (PC3-12800) CL9 Desktop Memory Kit (Two 4GB Memory Modules)
4 - Samsung Spinpoint F3R Raid Class 1TB SATA 3.0Gb/s (RAID main HDD)
1 - Zotac ZT-40502-10L GeForce GTS 450 AMP! Edition 1024MB GDDR5 PCIe 2.0 x16 Video Card
1 - SIIG USB Bay Media Card Reader
1 - Samsung SH-B123L 12X BD Combo Drive OEM
1 - Samsung LightScribe 22x DVD±RW Burner with Dual/Double Layer Support OEM
1 - Cooler Master V6GT Universal CPU Cooler
1 - Windows 7 Professional OEM

Thoughts? If my best choice is a new motherboard or RAID card, any recommendations would be appreciated.

 

[DeepFrz97]

I forgot to add that I am running the latest BIOS for the motherboard.

 

[janas19]

Does this mobo have any power savings features in BIOS?

 

[dbailey]

I'd check to see if it is automatically doing something at night like defrags, scan's etc. Manually kick one off during the daytime and if it happens then, voila. Turn that "feature" off.