# Core i7 920



## floydfan (Oct 18, 2006)

I want to try oc'ing my i7 920. What would be the highest oc I could get with very good cooling, possibly water?


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## greenbrucelee (Apr 24, 2007)

That question can't be answered because all cpu's are different (even the same make). It also depends on the rest of your components like your motherboard and ram of which you have some decent components.

Getting a 30 % increase with decent cooling should be possible.

I wouldn't bother with water cooling if I were you, it's a waste of time imo and water and electricity don't mix if it goes wrong.


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## floydfan (Oct 18, 2006)

30% seems rather conservative, it seems that 4ghz+ is pretty common with i7 on air.


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## Get Rekd (Sep 19, 2009)

With those computer specs, you don't even need to overclock it. That being said, it is obvious you think your a badass and wish to prove it. If you think your computer can handle the heat, I would suggest trying to get it to around 4.2ghz.


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## kyle g lied (Nov 15, 2008)

get a new i7. get the lynnfield 2.93ghz processor. thats what i have. it has better turbo, and if you are running a single thread the other 7 cores can automatically over clock the one core with more of a multiplier then your core i7. 
bloomfield 920's turbo 1/1/1/2
lyynfield 870's turbo 2/2/4/5


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## Phædrus241 (Mar 28, 2009)

The new core i5 and i7 CPUs use a different CPU socket, LGA1156 rather than LGA1366. I rather doubt that the user wishes to replace half of his computer for a decrease in performance (even with turbo, i7 850 is slightly slower than i7 920) and negligible overclocking benefits.


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## greenbrucelee (Apr 24, 2007)

floydfan said:


> 30% seems rather conservative, it seems that 4ghz+ is pretty common with i7 on air.


like I said all cpus are different. Some people like me can get my E8400 from 3GHz to 4GHz no problem some people can't get it passed 3.6GHz

Lots of cpus get made at same time and come from the same die you may find that one at the top will overclock well whilst one in the middle might not and one at the bottom might overclock well.

That is why I say you should be able to get to 30% but other than that I can't tell you as overclocking is all about experiementing and taking your time to get the best results.


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## kyle g lied (Nov 15, 2008)

with the turbo is the i7 870 faster then the i7 920? even thought the i7 920 is clocked higher. the 870 has much better turbo


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## greenbrucelee (Apr 24, 2007)

the 920 is the one for i7s but still a waste of time since ddr3 is still slow, expensive and buggy.


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## kyle g lied (Nov 15, 2008)

i won my lynnfield 870, 8gb ddr3, 2gb evga nvidia gddr3, 1 terabyte hd, p55 motherboard in a contest. ddr3 ram sure seems fast to me


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## greenbrucelee (Apr 24, 2007)

yeah it will do but it's not as fast as it could be, it'll be 1 or 2 more years before they get it sorted and by then the i5 will be mainstream and 6 core cpus will be coming out.


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## Phædrus241 (Mar 28, 2009)

> i won my lynnfield 870, 8gb ddr3, 2gb evga nvidia gddr3, 1 terabyte hd, p55 motherboard in a contest. ddr3 ram sure seems fast to me


Congrats. Personally, I would have sold it for the value of the parts and used it to build a better designed system (either the classic P45+E8500+4GB DDR2+high end graphics card, or P55+i5 750+4GB DDR3+high end graphics card... probably a Radeon 5850 or 5870). But it's a powerful rig, no denying that.


DDR3 has very high clock speed, higher than DDR2 can reach, but also very high latencies which limits its MOPS (memory operations per second).

The way to estimate MOPS to within 10% is to take the physical clock speed (reported clock speed and divide by two), then divide by the CAS latency. So:

My DDR2 1066 CL5:
533 / 5 = 106.6 million MOPS
A set of DDR3 1600 CL9:
800 / 9 = 88.9 million MOPS

Therefore, my mid-upper-range DDR2 RAM is faster than average DDR3 RAM.


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## greenbrucelee (Apr 24, 2007)

Thanks for that Phaedrus2401 I couldn't remember the caluclation bu was going to type something similar.


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## kyle g lied (Nov 15, 2008)

ok so my ram has a reported clock speed of 1333MHz. so i divide that by two, and how to i figure out the CAS latency to finish the calculation?


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## Phædrus241 (Mar 28, 2009)

You have to look it up on the website, or locate the RAM timings section in your BIOS. For DDR3 1333 a CL of 9 is fairly typical, 7 or 8 might be seen on higher-end kits.

If it has CL7 that gives 95.2 MMOPS. CL9 would be 74.1 MMOPS.



But really, memory speed has fairly little impact on performance. Any difference less than 20MMOPS would be barely noticeable.


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## kyle g lied (Nov 15, 2008)

also couldn't i just upgrade my ddr3 ram when they come out with lower CAS latency ram?


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## Phædrus241 (Mar 28, 2009)

Of course. There is lower-latency DDR3 out right now (down to CL7), and also higher-clock speed DDR3 (fastest I've seen was a G.Skill kit that claimed DDR3 2200 CL7. It's discontinued, though). It's more expensive, though, so your call.


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## kyle g lied (Nov 15, 2008)

ill stick with mine. it can run any game i want to play easily, halo 2 runs on 1650 x 1050 perfectly. very smooth and fast fps. 
i think it is cool that i have a computer thats better then the xbox 360 haha


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## Phædrus241 (Mar 28, 2009)

Yup, no need to go overboard.

Though Halo 2 isn't really a taxing game at all. The Xbox 360 has a mid-range triple core CPU (by today's standards) and a graphics card based on the Radeon 2000 series. My computer is literally twice as powerful as a 360, and cost about $700, give or take. Your computer can handle a lot more than you're throwing at it.


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## kyle g lied (Nov 15, 2008)

also if you are thinking of getting a new computer case i would go with this cm storm sniper.
http://www.testfreaks.com/blog/review/cooler-master-cm-storm-sniper-pc-case/
its big but it cools down very easily and has a fan controller on it. feels like an are conditioner when its up all the way, and not loud at all. i love how easy and accesible everything is on the front panel


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## kyle g lied (Nov 15, 2008)

well its always nice to know it can handle more too. i havent tried the blue ray player yet. very eager to try that.
what is your windows experience index score?
i dont think it can rate mine completely because it maxes everything out at 5.9


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## Phædrus241 (Mar 28, 2009)

5.7, everything is 5.9 but the CPU, which is the weakest part of my system. 

Windows 7 expands the system up to 7.9. I think when I used the beta that my GPU score went up to 6.5, CPU still the slowest at 5.7.


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## kyle g lied (Nov 15, 2008)

hmm can i download the beta version for the index score on vista home premium?

and you mentioned before you would get an i5 on a p55 with 4 gigs ddr3 but the i5 doesnt have the hyper threading technology that my i7 has.


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## kyle g lied (Nov 15, 2008)

i dont want to install windows 7 beta, like is there a way i can upgrade the experince score for vista?


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## Phædrus241 (Mar 28, 2009)

Hyperthreading does absolutely nothing for your gaming performance, at all. It might help if you're running VMware or doing video decoding or using AutoCAD, but not for gaming. The i5 750 also has a "turbo" function when running single and dual threaded applications (like first person shooter games) where one core is overclocked and the others underclocked, for better performance in programs that can't/don't use four cores.

I believe that in a Fallout 3 benchmark the Core i7 920 got about .3fps more than the i5 750, all else being equal. The i7 965 got .5fps more than that. Yay for $1000 CPUs.


I'll be brutally honest with you. If I'd won that computer in a contest, I would not even have turned it on. I would have immediately sold it on ebay as a "custom computer" for parts value + 10%, no warranty. Then used the proceeds to build an equivalent i5 or C2D build, and kept the savings. 

Since you got the computer essentially free, that's great and it's a decent computer. But if I were building a gaming computer, I would not base it on yours and would instead use components with a better "bang for the buck".


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## kyle g lied (Nov 15, 2008)

well the turbo for my core i7 lynnfield has better turbo ratios than both of the core i5's. and my computer also came with the 22inch lcd screen wich would knock a good portion off the retail value if i sold just the computer. i could buy one for just the same amount of money off newegg with a tiny bit better specs, however i dont play hardcore games on the computer. seems like you might though and all of your specs are under mine excpt for your ram, which does not make a big difference, according to you, and i have double the amount of ram as yours.


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## Get Rekd (Sep 19, 2009)

greenbrucelee said:


> yeah it will do but it's not as fast as it could be, it'll be 1 or 2 more years before they get it sorted and by then the i5 will be mainstream and 6 core cpus will be coming out.


I could see Intel and AMD skipping 6 cores cpus and going straight to 8 cores like the ps3.


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## greenbrucelee (Apr 24, 2007)

Get Rekd said:


> I could see Intel and AMD skipping 6 cores cpus and going straight to 8 cores like the ps3.


they might do but if they do the CPUs will be a lot more user friendly for the programmers than the cell the ps3 uses.


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## kyle g lied (Nov 15, 2008)

is the core i7's technically an 8 core?
i know it divides each processor into two logical processors making 8 visible.


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## greenbrucelee (Apr 24, 2007)

no its a true 4 core


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## floydfan (Oct 18, 2006)

6 core server cpus are already out from both intel and amd, and there will be an i9 6 core coming out this winter from intel. amd will also have a 6 core later in 2010. 

On topic, what is so bad about water cooling? It seems to be popular, and there doesn't seem to be significant risk unless it is set up incorrectly.


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## greenbrucelee (Apr 24, 2007)

floydfan said:


> 6 core server cpus are already out from both intel and amd, and there will be an i9 6 core coming out this winter from intel. amd will also have a 6 core later in 2010.
> 
> On topic, what is so bad about water cooling? It seems to be popular, and there doesn't seem to be significant risk unless it is set up incorrectly.


there's nothing bad with it. I just find that can actually get the same results with air cooled systems when overclocking plus when I was a kid I was taught water and electricity don't mix and that seems to have stuck :grin:


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## floydfan (Oct 18, 2006)

maybe that is true for premade solutions like a corsair or coolit, but a user assembled water cooling loop is far superior to anything that air can get from what I have read.


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## greenbrucelee (Apr 24, 2007)

floydfan said:


> maybe that is true for premade solutions like a corsair or coolit, but a user assembled water cooling loop is far superior to anything that air can get from what I have read.


sorry but that is incorrect, the only difference water cooling makes is that it's quiet.

A mate of mine has basically the same setup as me but he has the extreme version of my motherboard and water cooling.

I can get to 4GHz no problem with mine he starts to struggle at 3.82 where as I can go all the way to 4.2GHz and he can manage 4.06 before his system won't take it any more.


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## floydfan (Oct 18, 2006)

Those are just two different chips though. Wc can be quiter, but when talking about max cooling capacity, wc surpasses air by tons. If you run prime or linx on the same chip using air and water, the difference is enormous, 20c+ at same clocks and voltage.


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## greenbrucelee (Apr 24, 2007)

the operative words are CAN BE when saying water cooling is better at cooling than air. It doesn't always work like that. Trust me, so far to date (since I was 18, now 32) I have built over 100 computers, I have built water cooled systems and air cooled systems.

I would never own a water cooled system for myself.

I have seen air cooled systems that are cooler than water cooling systems the only difference is that they are louder although the buzz from the water pump can get annoying.


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## Phædrus241 (Mar 28, 2009)

Extremely high end air cooling _can_ match the cooling efficiency of water; it just sounds like a jet engine. If you really shell out you can get water cooling kits that outperform the best air cooling, but they're very expensive.


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## kyle g lied (Nov 15, 2008)

its not actual water in it either. i believe if it leaks it will not fry your motherboard or something drastic like that.


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## Phædrus241 (Mar 28, 2009)

It's usually distilled water. Actual water, which will fry your components. People with a bit more money who are more cautious use glycol. There is also oil submersion cooling.


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## greenbrucelee (Apr 24, 2007)

yep glycol is the one to use.


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## kyle g lied (Nov 15, 2008)

is there a way to tell if it is glycol or water?


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## greenbrucelee (Apr 24, 2007)

to be honest I'm not sure, they look the same and I woukdn't recommend drinking any.


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## kyle g lied (Nov 15, 2008)

hahaha if i post a pic link of my processor do you think you might be able to tell me?


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## Phædrus241 (Mar 28, 2009)

There really isn't a way to tell. Most water cooling rigs use a mix of distilled water and antifreeze (in which ethylene glycol is a major ingredient), usually mostly water. A few, as mentioned, use just the ethylene glycol. Since the liquids look the same, the only easy way to tell them apart is that ethylene glycol tastes sweet BUT because it's toxic we really, really don't recommend that as a test.


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