Technical > Overclocking / Modding > Non k cpu

Non k cpu

reply to jchambers28

Re: Non k cpu

reply to jchambers28
There is a 'limited unlock' on the multiplier of non-K CPU's.

I read that the magic number is 35, and I saw exactly this on the i5-2300 I put in my (ridiculously overpowered) HTPC this past weekend. Anything over 35 goes to 35, but 35x100 MHz for 3.5 GHz isn't bad, and it still turbo's beyond that IIRC.

OK looked into it and the magic number is 4 above the highest turbo. Since the 2300 can turbo up to 3.1 GHz, I could set the multiplier to 35. Also it appears that speed is the maximum, it doesn't turbo beyond that.

What it all amounts to is a fixed overclock of 400 MHz with the turbo boost profile maintained.

The non K SKUs have a limited unlocked multiplier. The terms used by Intel is a bit strange so some people may not be able to grasp the concept immediately. The limited unlocked SKUs will allow the user to overclock the CPU 4 "bins" above the maximum turbo frequency. "bin" should really be multiplier here because that's basically what it allows you to do: bump the multiplier by up to 4 above what turbo would give you normally.

Take the i5 2400 for example. The 2400 has a base frequency of 3100MHz and a maximum turbo frequency of 3400MHz (single active core). This processor will allow the user to overclock to 3800MHz via turbo (math is easy here because the base clock is always 100MHz).

I am trying to grasp the situation here. why is that you cant drive up the front side bus like any other cpu? Old school over clocking?. Is it me or is intel trying to get even more greedy lately.

It's the nature of the ring bus architecture.
You can still slightly OC the base clock (aka BCLK or FSB), but it will directly affect the IMC (integrated memory controller), south bridge, etc.

So yeah, OC'ing Sandy Bridge is different from the old style or traditional OC.
If you want to OC, get the K version, it's that simple.

which cost even more money. sounds like Intel wants wants OCing to be a feature that has to be paid for where is was free before. AMD should be taking notes here.

Sheesh, you can't win.

Intel locks the multipliers and people bitch that it's locked and they have to screw around with the FSB, memory dividers, OC'ing the PCI bus, etc, etc.

Then they release chips SPECIFICALLY designed to OC, and people bitch about it costing more money.

Let's do the math, shall we? (Note: all prices taken from newegg for apples-to-apples comparison).

Intel i5 2500: $209.99
Intel i5 2500k: $224.99

The 2500 is 3.3 GHz with 3.7 GHz turbo and can go up "4 bins" to 4.1 GHz, tops.
The 2500k is also 3.3 GHz with 3.7 GHz turbo, but since you can change the multiplier you can go up as high as your cooling/thermal and voltages can go. Let's pick a conservative 4.5 GHz.

Thus the 2500 in terms of MHz per dollar is: 4100/209.99 = $19.52 per MHz.

The 2500k in terms of MHz per dollar is (again, conservatively): 4500/224.99 = $20.00 per MHz.

So we're talking about a $15 difference and a MINIMUM of 400 MHz more out of the K cpu over the non-K. So why are you complaining? If you want to overclock, drop the (whopping) extra $15. If you don't, save yourself $15 and go buy yourself $15 worth of booze.

*edit* And personally, I like this scheme. The chances you will get a good OC on a K CPU is very good. In the past, it was a crap shoot (other than finding out which specific steppings OC the best, but sometimes you can't even be sure which stepping you're buying!).

reply to jchambers28

Wish I could thumbs that As such, I will just reply and give you the public props. Great post.
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"Women. Can't live with 'em, pass the beer nuts." -Norm

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