i7 950: no turbo?

[Gendo]

I was just checking out the 950 on hwbot and I noticed everybody is running with multi 23. According to Intel the 950 should have multi of 23 so with turbo that would be 24 right?

Intel specs:
i7 940: http://processorfinder.intel.com/det...px?sSpec=SLBCK
i7 950: http://processorfinder.intel.com/det...px?sSpec=SLBEN

As seen in those links the 940 has a multi of 22 (+1 with turbo) and the 950 has 23 (+1 with turbo?) but I don't see any one running 24 with their 950.

Pardon me if it's something really simple I'm not seeing

[unclewebb]

The maximum practical 24/7 type overclock is around 4400 MHz - 4500 MHz and a good motherboard can run a BCLK of 200 so their isn't much use for a multiplier beyond 23. I seem to recall the 24X needing too much voltage for stability. I know rge likes running his 950 at 23X. I think he's saving 24X for the winter when he's going to do some serious overclocking.

[Gendo]

I'm not talking about 24/7 oc's here. I'm talking about people running the 950 under ln2 @5Ghz+ with multi 23.

So it's not that the 950 doesn't have the 24 option, it just doesn't work right?

[unclewebb]

5GHz with a 23 multi is still only a BCLK of 217 which isn't a problem for a good motherboard. I think it comes back to stability. Better stability with a 23 multi compared to the 24. These CPUs work fine at 24X and even 25X when only a single core is enabled in the bios.

Here's some testing by rge:

http://www.xtremesystems.org/forums/...0&postcount=96

Contact him if you want to know what multiplier he likes best and why.

[ReverendMaynard]

I'm not talking about 24/7 oc's here. I'm talking about people running the 950 under ln2 @5Ghz+ with multi 23.

So it's not that the 950 doesn't have the 24 option, it just doesn't work right?

The few people I know that tried the 24x found that it was buggy as hell.

[Gendo]

Aah that explains it Glad I went for Xeon W3540 then and not 950

[Leeghoofd]

Even multies remain the ....

[ReverendMaynard]

Even multies remain the ....

...Satan of all i7 overclocking?

[Gendo]

So are there more people with a 950 that can confirm that the turbo is crap?

[Nanometer]

what you mean 24 is bad? I haven't had issues using 24. All the way to to 4.5 GHz prime stable... but now I'm having bclck stability or ram stability problems..

[DEVIL K-ce]

So are there more people with a 950 that can confirm that the turbo is crap?

On MOA 2009 PL We used 950 + Eclipse, when We set turbo to enabled it's working only at boot, not in windows ; at full load.

[Nanometer]

no issues at all.. maybe I got lucky

[Leeghoofd]

Works here, but harder to stabilise like all even multies on I7

[rge]

Benching with 23 multi, I can do 5 ghz for 2-3 seconds using 14C ambients (vent of a/c to rad intake) but not stable enough to capture cpuz validate yet, I can validate 4.95, but already did that with my i940 (sig). When winter comes I will get 5+ghz easy with subzero winter ambients outside, which is what I needed to get 4.9+ on my i940.

With 24 multi I max out at ~4.85 with same vcore, vtt, ambient, or about 150 mhz lower. People using LN2 have complained of same thing, get 150-300+mhz higher using 23 multi than 24 multi for max MHZ.

For 24/7, same issue, I can bench 3D all day with 4.62 Ghz with 1.46vcore, 1.46vtt using 23 multi (http://service.futuremark.com/compare?3dm06=11376865), or 4.7 if use higher vcore but only 50% 3d runs make it, depending on temps. Using 24 multi I cant get 4600 stable unless I increase vcore about 5 notches, even then still crashes sometimes in a 3d run.

People are benching with 23 multi, because 24 multi sucks. Once you get down to around 4.4mhz on mine, the vcore requirement is not as different, just 2-3 notches more for 24 multi than 23 for same mhz.