Maximum PC

Hey all,
I have the following build:

Intel I5-2500K 3.30 GHZ 6M LGA 1155
1TB SATA III 7200 RPM 3.5" HARD DRIVE
4 GB DDR3/ 1600 MHZ MEMORY
ASETEK 510LC 120MM WATERCOOLER
ASUS P67 SABERTOOTH Intel P67 2WAYS SLI/CROSSFIRE DDR
XTREMEGEAR 800 WATT POWER SUPPLY
AEROCOOL TOUCH 2000 DUAL BAY TOUCH SCREEN FAN CONTROL
EVGA GTX560 TI 1GB GDDR5 PCI-E DIRCTX

I want to increase the I5 from a 3.3 GHZ to a 4.0 GHZ for my first time messing with OC. I have gone on line for a step by step guide but am wondering if the ASUS OC Tuner would be a better choice for my first attempt. Any suggestions from the veterns?

OK, tried the ASUS OC Tuner and got nothing. So back to trying to find a step by step guide for OC that makes sense.

I may be old fashioned, but I prefer a BIOS/UEFI overclock personally.

Since Sandy Bridge architecture includes a clock generator on-die with the CPU and support components, the more traditional method of FSB/BCLK overclocking is a thing of the past. You need only concern yourself with the multiplier.

The i5-2500k bus/core ratio is 33 I believe, which means the bus would be 100Mhz. Head into the BIOS/UEFI and change the multiplier to 40. There's your 4Ghz overclock. Not too tough, eh?

Here's the real question though. Are you fine with speed-step and power saving features, or do you want the CPU @ 4Ghz all the time?

Pretty much this. You can safely bump if up to 4.4Ghz (multiplier of 44) provided you have adequate cooling without too much issue. The voltage is automatically determined among other things. From here you may need to change other parameters.

For the downclocking, default settings Windows will take care of this. The power saving issues aren't much of an issue since this is a relativity low OC.

Hey Airhead. If you look just a couple posts down on this thread I had a thread going discussing my overlclocking of an i5-2500k to around 4.6GHz stable off air on an AsRock motherboard (a board closely related to Asus) including what settings I used. Check it out.

Bottom line though if all you want is 4.0GHz try just try setting the multiplier to 40 and leave everything else the same, often the i5-2500k's are so good they will do that off stock voltages and still be stable! Thing is though without changing some settings you might find that the processor throttles down a bit under load so you may have to do some tweaking.

I have a water cooling system so am not too concerned about heat with what I want to do. I willl try just adjusting the multiplier first. Thing is when I look at the multiplier in the bios it says it is at 40. When I run CPU-Z it gives me two numbers one at x16 and the other at x40. Is this the step mentioned above? If so how do I change it so it just runs with the x40 setting?

Your first step should be to disable Enhanced Intel Speed-Step Technology (probably abbreviated EIST in BIOS). You may also consider disabling C1E in power management if you plan on running the CPU overclocked all the time.

@grev Nice OC, personally I like the voltage a low as possible. Uses less energy and it runs cooler. I would keep it at 4.5 because of that.

@Stormdrake What you are seeing is SpeedStep which drops the multipler when you are idle. Almost any load on the system will cause it to boost back to a 40 multipler. For OCing purposes, again you don't have to disable them. It is useful sometimes. If you do want it at the highest multipler all the time, search for power options in Windows. This will allow you to select a high-performance power plan.

Thank you all!
The speedstep is what was messing me up. I was running CPU-Z with nothing else going on so it was showing me the x16 speed and not the x40. I will try running CPU-Z while I have STOR up and going and see what it tells me then.
Thanks again

Personally I kept speedstep on. I mean I don't see why having the processor throttle down when its not in heavy use is a bad thing, it drops the power consumption down to like 10 watts and lets the heat drop crazy fast. I suppose there might be that split second it takes to throttle back up when a load kicks in but I'm not sure if that delay would be at all noticeble. Therefore in my OC I kept C1E and speedstep enabled and its still perfectly stable.