Loss of Overclock/Occassional Freezes

I recently purchased a DS rig back in March, had it for a little over 2 months now. Everythings run great so far until about a month ago. I had 2 system freezes happen back-to-back. I ran all my virsus scans( Avast and Webroot ) and even windows defender. Didn't find any issues. Then i thought maybe my drivers weren't up to date. All of the ones I could think of were when I checked. Since then everythings run great ( this rig crushes SCII and FFXIV, even though it sucks lol) and im about to test Crysis 2 on it. Last night it froze up playing SCII, so i attempted to restart it. Reset button didn't reset it. So i turned the power off. Attempted to turn it back on and it froze on bootup. Turned it off again and it worked this time, but the boot screen said my overclock was lost, something to that effect. Went into the BIOS and sure enough, no overclock. I've run all my virsus scans again today and even de-fraged both my SS and HDD ( SSD was 7% de-fraged ) and no hiccups at all today.

I want to trust myself to overclock it again myself but I've never done it personally. I'm pretty comp savvy and I could probably do it no problem, but I wanted to consult the forums first. Also maybe ask what could have caused my weird freezing issue last night? Thanks in advance, and I'll post my specs below.

System Configuration:
Chassis Model: Special Deal Hot Seller - HAF 922
Exterior Finish: - Standard Factory Finish
Trim Accents: - Standard Factory Finish
Processor: Intel Core i7 2600K 3.40GHz (Unlocked CPU for Extreme Overclocking) (Quad Core)
Motherboard: ASUS P8P67-M PRO (Intel P67 Chipset) (Features USB 3.0 and SATA 6Gb/s)
System Memory: 8GB DDR3 1600MHz Digital Storm Certified Performance Series (Highly Recommended) (Hand Tested)
Power Supply: 750W Corsair TX (Dual SLI Compatible)
Expansion Bay: - No Thanks
Hard Drive Set 1: Operating System: 1x (80GB Solid State (By: Intel) (Model: X25-M MLC Edition) (Extreme Performance)
Set 1 Raid Options: - No Thanks
Hard Drive Set 2: Multimedia\Data: 1x (1TB Hitachi/Seagate (7200 RPM) (32MB Cache)
Hard Drive Set 3: Backup\Misc.: - No Thanks
Optical Drive 1: DVD-R/RW/CD-R/RW (DVD Writer 24x / CD-Writer 48x) (LightScribe Edition)
Optical Drive 2: - No Thanks
Internet Access: High Speed Network Port (Supports High-Speed Cable / DSL / Network Connections)
Video Card(s): 1x NVIDIA GeForce GTX 570 1.2GB (Includes PhysX Technology)
Add-on Card: - No Thanks
Sound Card: Auzen X-Fi Bravura 7.1 (PCI-Express Slot Based)
Extreme Cooling: AIR: Stage 1: Noctua NH-U12P SE Dual 120mm Fans High Performance Cooler
H20 Tube Color: - Not Applicable, I do not have a FrostChill or Sub-Zero LCS Cooling System Selected
Chassis Airflow: Standard Factory Chassis Fans
Internal Lighting: Internal Chassis Lighting System (Green)
Enhancements: - No Thanks
Chassis Mods: - No Thanks
Noise Reduction: - No Thanks
CPU Boost: FREE: Overclock the processor between 3.6GHz to 3.9GHz
Graphics Boost: - No Thanks, Please do not overclock my video card(s)
Memory Boost: - No Thanks, Please do not overclock my memory
OS Boost: - No Thanks, Please do not tweak the services on the operating system
Windows OS: Microsoft Windows 7 Home Premium (64-Bit Edition)
Recovery Tools: Windows Recovery Toolkit (Bundled with Windows 7 CD)
Virus Protection: - No Thanks
Office: - No Thanks
Benchmarking: - No Thanks
Pre-Install Game: FREE: Hot-selling game with a NVIDIA GeForce GTS 250 or above graphics card
Display: - No Thanks
Surge Shield: - No Thanks
Speakers: - No Thanks
Keyboard: Logitech G15 Gaming USB Desktop (Multimedia Keyboard)
Mouse: Cooler Master  Sentinel Advance Gaming Mouse (High-Speed Gaming Grade)
External Storage: - No Thanks
Exclusive T-Shirt: - No Thanks
Priority Build: - No Thanks, Ship Within 5-15 Business Days After Order Is Successfully Processed
Warranty: Life-time Expert Customer Care with 3 Year Limited Warranty

Any help would be awesome

agreed thats what i'm using to oc my pc soon.
also don't defrag ssds it just wears them down, trim will keep it fast for you.

trim is something that will happen automaticly. its a service that clears free space. the mobo handles it.

close enough :P