Printable View
I haven't touched QPI PLL, i've still to find out what CPU / QPU PLL does.
All i did was set 1.44v QPI, remove other bottlenecks (low cpu multi, memory, 17x uncore 18x QPI). I went straight from stock to 1.44v aswell, so i'm not sure how much i actually need, it could be less.
Maybe chips will vary in max stable bclk as much as they do in max stable cpu clock?
P.s i've not seen any evidence that vcore affects QPI. I had 1.275v set when i was 1.44v QPI + 213mhz stable.
But isn't Intel's suggested limit for QPI/vtt 1.35V? Why should this limit not be taken into account, when the limit on vcore (1.55) is much higher than what most people are running on their rigs?Quote:
Originally Posted by Xello
I can't cross BCLK 160 with 1.35 QPI.
because 1.55 comes with a massive amount of heat
its a suggestion as well, not sure if you saw the 2000mhz corsair cas7 preview but they require 1.65QPI/VTT at this point atleast
dejanh, I'm having some trouble with the ratios theory here.
I've had two different settings pass 12h ond 8h Prime95 stable on two different bios versions and it definitely doesn't follow the "rule" you stated.
Setup number one does not follow the rule but it's stable. Setup number 2 does follow the rule and is also stable. The one constant is that the QPI stays below the 4GHz threshold. Could that be all that's required?
I've also tried on bios F4k and I've been having some stability issues with BOINC that I haven't worked out yet. Of course, all of this on the stock cooler doesn't help.
1) Bios F2 - Bclk 160 - RAM 10x - UC 20x - QPI 18x
http://img.photobucket.com/albums/v3...g?t=1229623815
2) Bios F4l - Bclk 200 - RAM 8x - UC 16x - QPI 18x
http://img.photobucket.com/albums/v3...g?t=1229623816
Are you sure it's not dram voltage? 1.65 QPI is damn high.Quote:
Originally Posted by Bobbylite
EDIT: I checked, you're right. I still am afraid, we're in testing stages with this new platform. I hope these QPI voltages are not deleterious for the system...
It is 1.65v QPI in their profile. Kind of strange, and probably not an option for the aircooled crowd.Quote:
Originally Posted by Cooperdale
I've got good air cooling, but I still can't bring myself to go over 1.35 QPI. I'm too afraid of making the system's life very short...
Does QPI involve the cpu temp, or the system temp?
I've gone up to 1.65 VTT myself, although, since I learned (not too long ago) that Intel says 1.35 max, I've dropped down to 1.4 and under. Im not opposed to going over 1.35, as it helps stability, but I also not going to EVER go over 1.55 again...
Mine is at 1.4125 atm, probably could lower but will need to be raised as I keep pushing anyways
I've gone as far as 1.83 vtt to try to boot into 220 Bclk,
I've settled for about 1.35-1.4 as my 24/7 setting.
Glad to have some feedback! :) The more discussion stirs up, the more we can dissect the intricate aspects of i7 overclocking ;)Quote:
Originally Posted by zlojack
1. In terms of the QPI having to stay below 4GHz, yes, this is definitely correct. QPI higher than 4GHz will not run on 99.9% of the boards and chips. This is critical.
2. In terms of the Uncore:QPI ratio of 8:9...I think I edited the original post the next day to reflect some people saying "I'm running Uncore higher than my QPI". While this is very possible I found that this is (a) not stable when dealing with high clocks (3.9GHz+) at least in my test setup, and (b) not exactly an option on i7 920 and i7 940 when you get to high clocks at all as you are driving your DRAM, Uncore, and QPI all based on the same high BCLK. If you use a 200MHz BCLK your lowest option for QPI is 3600MHz which is already getting up there. I tried running DRAM at 1800MHz with this and the Uncore with 3600MHz and I was completly unstable. Lowering the memory to 1600MHz (more within the ratio I defined) made the system more stable. Same holds up if I go to 180MHz BCLK with a 23x multiplier (turbo on i7 940). I put the QPI below Uncore to the test by assigning a 18x multiplier (3240MHz) to QPI and running my DRAM at 1800MHz (3600MHz Uncore). The system was unstable. Then I restored the QPI ratio to 22x for 3960MHz and the system was once again stable.
Overall, the 8:9 Uncore:QPI is not a hard rule. I just found it to be a "safe" rule in my testing. Adding to it you have to consider that Intel does not randomly spec out their processors. If they felt that ratios between different components of the CPU could be different, they probably would have set them up different, so there must be some reasoning behind their factory set ratios. They had the option easily to make the Uncore and QPI run at the same speed from the factory, or even higher, but they chose not to. I believe I found why they did that through my testing, and I do not think that it is just becase there is *maybe* no performance increase in running Uncore more than 2x DRAM. Kind of like with AMD where on the X2 processors you had to keep your HT as close as possible to 1GHz to balance stability and performance. Much higher than 1GHz and poof, the system dies, much lower and you are sacrificing performance.
cpu multi 20Quote:
Originally Posted by Lukee
qpi multi 26
uncore multi 16 (or even auto.. i've had it running 4000mhz just fine)
memory multi 8x (to get rid of that as a limiting factor)
cpu voltage 1.55 (also to eliminate that as a factor)
qpi/vtt v 1.55
cpu pll 1.9
ioh core (or whatever uncore voltage was) 1.45
tried with load line calibration on and off
clock skew's upped 50ps
WILL NOT RUN 200 BCLOCK... and i'm pissed... i was hoping to hit 26k 3dmark06 before shipping off these 260's i just sold.. but looks like that ain't gonna happen!
Got my max stable bclk and 23x cpu clock, time for some RAM!
How are you guys finding your 1.65v rated kits when it comes to overclocking? I have virtually the same Corsair kit as i had on my X48 only that was 2x2gb 1.8v and now it's 3x2gb 1.65v. I had no problems with the old kit going to 1.99v and being 1800mhz stable, i'm not sure what to expect from the new kit.
Is it still reasonable to pump an extra .2v into the 1.65v kits and get some performance gains, or should we be more conservative now? I don't want to just jump start it with 1.85v incase i fry something ;)
1.85 sounds a bit much IMO maybe like 1.74-1.8?
Yeah just an example :)Quote:
Originally Posted by Bobbylite
For the previous kit i was able to judge it based on several reviews, but i can't find a single review for the new kit anywhere :mad:
That qpi mult, is that a typo? should it be 36x?Quote:
Originally Posted by nosboost300
Ok, try this..
uncore multi - 15x
mem multi - 6x
I know.. you don't want to lower it.. just try it first and see if you can get that stable!!
You can probably lower Vcore to like 1.45 or so. and you can turn on turbo :)
I had the same problem you did and those adjustments allowed me to stabilize at 200 Bclk.
okay... well i'm running 197 b clock right now... i managed a 195 3dmark run.. but my freakin qpi is 1.6v now.. seems kinda scary is it not???
anywho.. i'm going to run 3dmark06... if i'm not back in about 7 minutes (i think thats how long 3dmark06 was...) then my computer screwed up.. haha
and yes that was a typo :p
197 qpi success!
Cool!!!! What are your settings?Quote:
Originally Posted by Movieman
I have the Corsair Dominator XMS3 1.65V 3x2GB 1600MHz kit and I can easily get 1800MHz out of it without any voltage tweaks really. It runs 1800MHz just as it runs 1600MHz at 1.65V. Going to 1900MHz I have to up the voltage to about 1.68V - 1.7V, but that is it. Right now I am running them at 1.65V 1800MHz.Quote:
Originally Posted by Xello
Wow that is a reference to an old post, hehe. Anyway, his settings won't matter to you. Every board is different from what I can tell so far. With Asus look only for Asus-specific settings. Just as an example, R2E overvolts every voltage you set, but the Gigabyte boards seem to undervolt.Quote:
Originally Posted by skypx
What are your timings for both 1600 and 1800?Quote:
Originally Posted by dejanh
Very good response!Quote:
Originally Posted by dejanh
Thanks again for your input.
I'm going to continue to do more testing and once I get proper cooling I'll be able to start eliminating some factors from the stability equation (at least some heat!)
http://i7.photobucket.com/albums/y26...ost300/26k.png
198 bclk... still can't get 200...
Has anyone seen anthing about whether ASUS is going to be releasing any BIOS updates which will let us adjust the QPI and/or memory multipliers downwards? I think that it's holding my rig back significantly. I have 4.0Ghz rock stable at 1.36v with HT on but have to use a Bclk of 211 and a 19x multiplier to do it.
Yeah... I guess it's possible that everyone here running over that spec including myself will be shelling out for a new chip in a few months. I'm hoping not :) Also, there is Saaya's VTT graveyard thread which has some info on the first posts of rigs which have been running at certain settings, one of which is 1.45v. If i check that post one day and read that the cpu is bust, i'll reduce mine instantly and pray!Quote:
Originally Posted by Cooperdale
Cool, i've started with 1648mhz and 2 hour stable so i'll increase bclk 3 or 4 points and see what i can get before i increase V's. I assume they're still samsung IC's, they appear to overclock extremely well. If they can go to the 1800mhz~ mark that will make the final i7 OC alot better!Quote:
Originally Posted by dejanh
Is there a way to find out what your memory's stock timings are? The board has setting 1T for me this whole time and i didn't realize, i think it's meant to be 2T for stock, because under cpu-z SPD tab under the XMP-1600 profile it has 2T CR . All my sub-timings are on Auto in bios, i have 1.66v manually and 9-9-9-24 manually.
There's a 'performance' setting in bios where you can choose Standard, Turbo or Extreme, it's Turbo on default, is that something to do with memory sub-timings? Perhaps that's why i'm on 1T.
Anyway since it's setting 1T i was wondering if there might be any other timings it's tuning without my say-so, i really want them all @ stock while i find max clocks, i'll find timings later. CPU Tweaker is good for showing you all your timings in windows, but i don't know if the numbers i'm seeing are @ stock or not.
8-8-8-24-2T (default timings, need to tighten still so may require a bit more volts than 1.65)Quote:
Originally Posted by Lukee
:) I'm still baffled by one thing though...turbo and when it shuts off. If I Prime and the temp hits 85C turbo shuts off but the CPU does not crash, but if I just run some application (like Vantage CPU test) and the temp goes to 85C the system hardlocks. But this is only on 23x180MHz, not 23x179MHz :rofl:Quote:
Originally Posted by zlojack
I would not hold my breath on this. Nobody is doing it, so I do not think Asus will either...maybe post it as a Feedback and Suggestion on Asus forums?Quote:
Originally Posted by Classic Satch
Dominators are 8-8-8-24-2T stock.Quote:
Originally Posted by Xello