I've tried this several ways:
Using EasyTune6. I choose any one of the presets (1,2, well, haven't tried 3) , it says restart now or later. Have tried both. When it boots it will power up, shut down, power up and it'll be unclocked.
Using Bios, tried 34, 35,...38, 40 several different multipliers. Same as above, it restarts 1 or multiple times and is unclocked when it finally boots. (When I change it in BIOS it says 'failed to start-OC...' and it's back at 3.3)
And last I have tried Touch BIOS. Again, set my multiplier, starting low... 34, 35... Save... reboot. It doesn't shut off , it fires right up, but still no OC if I check in Touch Bios.
Temp on case and CPU is generally about 30*C idle, 40-maybe 50*C gaming
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z68ap-d3 (Updated Bios to FD)
i5 2500 K 3.3 (turbo 3.7 which works fine-it's constantly adjusting)
corsair 1600 DDR5 4Gx2 (Which always shows in BIOS as 1333)
WD Raptor and WD Caviar
650W Seagate PSU
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I haven't tried turning off turbo but from what I've seen you don't need to unless you go above 4.5ghz. I'd like to see 4.0, maybe 4.3 and still have the system lower itself when it doesn't need it.
So far the system is really nice, stable, fast and smooth so it's not like I HAVE to OC. But I got the k model so I could.