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Which i7 motherboards can support 21x multi LOCK?

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doz

Member
Joined
Nov 30, 2002
Location
Las Vegas, NV
I think I could do alot more with this CPU (1.21v FULLY stable @ 4ghz) with a board that had a 21x multi lock. Also, this board is ROCK solid, but doesnt like higher FSB unfortunately. Thinking about another board, but having a 21x multi lock would be nice. Which boards support this?
 
No board can do it. Look for BIOS mod for it. :) I'm not even using a 20 multi, heh.

_____________________
Intel i7 920 [211] BCLK x 19 = 4.0 GHz @ [1.4500] CPU Voltage & [1.35000] QPI/DRAM Uncore Voltage, Batch 3836A394
3 x 1GB G.SKIL DDR3 1333 (PC3 10666) [DDR3-1691MHz] 10-10-10-24 @ 1.64 DRAM Bus Voltage
ASUS P6T Deluxe v.1 [LGA 1366 Intel X58] BIOS 1102
Thermalright Ultra-120 eXtreme 1366 RT with 120mm Scythe S-Flex F fan
ASUS EAH4850 TOP Radeon HD 4850 512MB @ 680 MHz GPU & 2100 MHz Memory
Antec nine hundred case, two front 120mm fans, one back 120mm Fan, one top 200mm fan
Corsair CMPSU-750TX 750W

http://www.ocforums.com/showthread.php?t=595403
 
There were a few people claiming they could lock 21x and it would run all 4 cores?? Ive seen this from multiple people as well. I was always under the impression you couldnt force 21x and it only boosted 1 or 2 cores.
 
Uh....many boards do it...like this. It is all cores. You can't use Turbo when using this though.:

systemh.jpg


Here is the clock on each core:

turboh.jpg


Under load, they are all 21.00 even.
 
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Is that a modded Asus BIOS that locks the multi at 21, or does your multi go down to 20 when the machine is stressed?
 
No sir. That BIOS is only for the Deluxe. Yes this throttles @ 4.3 and that is what the modded BIOS fixes. Since I can't get that...well. It doesn't go down to 20x, but it jumps everywhere from 20.8-21. I had about 30 passes of Linx at 205x21, but it was aggravating seeing the speed go anywhere from 4265 to 4300.

Just the latest Asus BIOS:

bioso.jpg
 
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Im not worried about throttling down, I just wanted a board that would lock in 21x multi.
 
You use W/C, so that helps. It can throttle at a lower speed when the temps get too hot. My temps were barely 70c at 4.3, but I was told it was the 1.35v causing it, which really isn't high.
 
Intel (R) Turbo Mode Tech or in later BIOS versions: Intel(R) SpeedStep(TM) Tech [Disabled] This increases the multiplier by one if the temps are low enough but I figure the OC may not be as stable when it does, so I changed it to [Disabled]



Is there a modded BIOS which locks the multiplier at 21? Otherwise, leaving this option on gives you 21 when things are moderate but it goes down to 20 as soon as you stress it. Overall I figure maybe things are not as stable as when you have a permanent multiplier.


I think the original poster was asking about a permanent 21, not SpeedStep which all mobos have.
 
This is a permanent multiplier. The throttle below 21x is the bug that the modded BIOS fixes for P6T Deluxe v2 boards. All of my cores stay at 21x constantly at 4.2. I can run Linx for hours and they all stay at 21x. The motherboard manufacturers have figured out a way to force the Turbo on all the time. I do not have EIST or Turbo enabled in the BIOS. The creater of Real Temp is the one that developed the I7 Turbo program to see if your system suffers for the bug or not. It reads the CPU multiplier more frequently than any other program so you can see if you have the bug. It only surfaces at high temps or higher v-cores.

You can read all about it here:

http://www.xtremesystems.org/forums/showthread.php?t=210480
 
'Modded' by definition is 'unofficial' so it would be going against mobo manufacturer specs. The intro i7 CPU is LOCKED at 20 multiplier max.


21 only only kicks in when things are moderate, which defeats the purpose, you need it to be at 21 when things are stressed. For all I know, there's no such thing as a permanent 21 with the intro i7 CPU. But theoretically if somehow someone made it stay at 21 permanently, it would be an unofficial mod, which as far as I know doesn't exist.

21 multiplier is just to show off your max OC, you can't actually use it when you need it the most, which is on a stressed machine, when the multiplier goes back down to 20, which is why I have the whole thing turned off, it just messes with your OC stability.
 
well i have no modded bios and i can use the 21x for the 920... i tring to figure out where this became some (moddable only) option... unless im just miss understanding what he means by 21x multi lock.
 
Your i7 920's 21 multiplier will go down to 20 if your machine is adequately stressed, True/False?

If true, then you don't have a permanent 21 multiplier.
 
From what I hear, many mobos allow you to set the CPU multi at 21x. With the proper BIOS (I forget which version the P6T Deluxe BIOS started supporting it), all you do is set the multi to 21x in the exact same manner as you would to set it to 18x or 19x. It disables Turbo, since it is basically forcing the i7 to run in Turbo mode all the time.

Also according to some of the guys at XS, many of those boards also allow you to turn off the additional Turbo throttling. Unfortunately, this is not possible on the P6T series without the use of a specially modified BIOS for the Deluxe. According to the ASUS rep who provided the BIOS for XS, the in-BIOS option for disabling Turbo throttling is a feature exclusive to their "premium" boards, such as the Rampage II Extreme.

From all I have read over there, the Turbo throttling occurs on the P6Ts under relatively high temps or while using around 1.4 Vcore. My own starts to throttle back very slightly (<0.2 multi) once one of the cores reaches around 84-85C. The throttling tends to be slight, but it is enough that it can cause instability. If I were on watercooling with this chip, it wouldn't be a problem because I can get away with using low voltage.

But anyway, yes, it is a 21x multi that can be set as such in the BIOS, and from what I hear you can turn off all throttling on certain boards.
 
Your i7 920's 21 multiplier will go down to 20 if your machine is adequately stressed, True/False?

If true, then you don't have a permanent 21 multiplier.

if i stress all four cores with prime95 or orthos it stays at 21x. that is when i set it to 21x in bios.
 
Well I'll be darned. I bought my ASUS P6T Deluxe v.1 on day 0 when it came out and didn't realize.

I updated to BIOS 1606 and I can now use the 21 multiplier! Not that I need it but I guess you can do this now!


Still, the poster above you Evilsizer says that unlike the 20 multi, if you go with 21 it will still be reduced somewhat which is not the point, the point is will it cause instability?...

So it's not about the 21 multi as much as it is about being able to lock it in just like the 20 multi is locked in, without it going down, even slightly.
 
Well I'll be darned. I bought my ASUS P6T Deluxe v.1 on day 0 when it came out and didn't realize.

I updated to BIOS 1606 and I can now use the 21 multiplier! Not that I need it but I guess you can do this now!


Still, the poster above you Evilsizer says that unlike the 20 multi, if you go with 21 it will still be reduced somewhat which is not the point, the point is will it cause instability?...

So it's not about the 21 multi as much as it is about being able to lock it in just like the 20 multi is locked in, without it going down, even slightly.

well i just updated the bios so i cant say if it more or less stable. then when i played with it the first time, as i left the QPI/fsb at stock speed. didnt have any stability issues there but ocing was another matter. just like others noted in the past best ocing was done on 19x. that is prolly different now with updated bios's. though im fine with only a 3.4ghz oc on my 920, rosie loves it too. though if i could get 4ghz on rosie would really love me then. my 920 at 3.4ghz ranked 3rd or was it 7th fastest pc. i would say 3rd or 4th for single cpu system on rosie stats. well im sure more people have i7's for rosie now and im getting OT. :bang head

things can change quickly when you havent been able to keep up...
 
Whole Lotta Rosie? I'd say the original poster's question now is not about the 21 multi but about how throttling back the 21 under stress can be turned off.
 
Whole Lotta Rosie? I'd say the original poster's question now is not about the 21 multi but about how throttling back the 21 under stress can be turned off.

would be the normal stuff C1E/EIST and there is some new one i cant recall atm... though all that throttling stuff is disabled in my bios...
 
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