Intel Core i7 990X Hexcore 1366 Page: 1

Intel Core i7-990X 


With so much hoo-hah surrounding the P67 chipset and the performance thereof, the X58 boards have been left somewhat in the shadows.

Not, by any stretch of the imagination, because that's where they belong, but rather the twin terrors of pricing, and target audience, have meant that your average consumer is much more taken by the "my first overclock" nature of the LGA1155 equipment than the enthusiast based LGA1366.

Despite this there is enormous amounts of life in the old girl yet and most of the big scores and jaw-dropping overclocks are dominated by the original Core i7.

With the forthcoming Socket 2011 on the horizon, Intel have brought their knowledge to bear on a swansong, a bit of an encore if you will. One last hurrah.

In exactly the same way that your favourite band doesn't play all their hits at the start of the show and their encore consists of a couple of b-sides from their days gigging in pubs that nobody have ever heard, Intel aren't going out with the whimper of a dual-core, non-HT revision or anything so watered-down.

No, today we have the all-singing, all-dancing, eye-wateringly pricey Core i7-990X Hex-Core to get our teeth into.  

Launch DateQ1'11
Processor Numberi7-990X
# of Cores6
# of Threads12
Clock Speed3.47 GHz
Max Turbo Frequency3.73 GHz
Intel® Smart Cache12 MB
Bus/Core Ratio24
Intel® QPI Speed4.8 GT/s
# of QPI Links1
Instruction Set64-bit
Instruction Set ExtensionsSSE4.2
Embedded Options AvailableNo
Supplemental SKUNo
Lithography32 nm
Max TDP135 W
VID Voltage Range



Intel® Turbo Boost TechnologyYes
Intel® Hyper-Threading TechnologyYes
Intel® Virtualization Technology (VT-x)Yes
Intel® Trusted Execution TechnologyNo
AES New InstructionsYes
Intel® 64Yes
Idle StatesYes
Enhanced Intel SpeedStep® TechnologyYes
Intel® Demand Based SwitchingNo
Thermal Monitoring TechnologiesNo
Execute Disable BitYes

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 Intel Core i7-990X

Test Setup

For testing purposes we're gathering the various Intel chips together for a final showdown, although as we know there are many people who will wonder why it's worth spending so much on a CPU, we're also including the latest P67 processor for you.

Intel Core i7-990X
Zotac GTX580 AMP!
ASUS Rampage III Extreme
Muskin Joule 1200w
6GB Mushkin Redline
Noctua NH-D14
Windows 7 Ultimate x64



As always the first task is to seek out the maximum stable BCLK, which in the case of our 990X was 220.5MHz. This should give us plenty to play with.

Intel Core i7-990X

Now as a rule of thumb once you find your maximum BCLK its generally difficult to get a high usable overclock with it, the 990X is one of the few processors that quash this rule as we managed to get a 4.8GHz overclock using that 220BCLK in conjunction with a 22 multiplier at just 1.4v.

Intel Core i7-990X  

And indeed it did. 200x20 is so easy and capable of running on such low volts that you could probably dispense with your power supply and just rub a balloon across your sweater now and again. Not strictly true, but away from the bleeding-edge overclocks the 990X definitely isn't a power-hungry monster.

However we're here for the big numbers, and after much sweating and tweaking the best I could manage was 5.2GHz, 208x25 with a vCore of 1.521v. Obviously this isn't something you would want to run 24/7 though.

Intel Core i7-990XCPU-Z Validation  

For benchmarking purposes we're running our 990X at a utterly stable 4.7GHz. 204x23, with a 1.45v CPU vCore. 4.7GHz of Hex-Core goodness sir? Don't mind if I do.

Intel Core i7-990X

Just for the sake of finding out we also set about finding the lowest stable volts that the 990X needed for a 200x20 4GHz overclock, the 970 needed 1.25v the 980x was thirstier wanting 1.35v but the 990X required a mind blowing 1.185v to be Prime95 stable! With these low volts and being cooled by the trusty NH-D14 temps did not go over 55c at full load over an 8 hour test period!  

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Intel Core i7-990X 

SiSoft Sandra

Processor Arithmetic

I think it's pretty obvious what is going to rule the roost throughout our testing, but in the Processor Arithmetic test the 2600K manages to make a good fist of things. Naturally the 980X is there or thereabouts and the older architecture and fewer cores of the i7-950 really hurt it.

Processor Multi-Media

Once into the Multi-Media test any potential smugness of the "buy a cheap 2600K" brigade is erased as the 990X is an atom bomb in a world of spears.

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Intel Core i7-990X 


CineBench R11.5 is definitely showing its age with regards to the OpenGL portion of the testing. As we get further away from the release of the benchmark the scores have become less and less consistent, or even usable as a gauge.

However the CPU test is as robust and useful as ever, and it's not exactly a shock that the 990X manages a eye-popping 11.98. Far and away the biggest score we've seen and to watch the image render on this chip is a sight to behold.


1 Billion calculations. 2 minutes. Do you really need any more information than that? No replacement for displacement the saying goes, and our heavily overclocked, hyper-threaded, hex-core wonder definitely proves that.


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Intel Core i7-990X 

3D Mark Vantage

As always 3D Mark Vantage is largely reliant upon the GPU, rather than amazing amounts of CPU horsepower. Nonetheless though we still have some tremendous scores with the 990X capable of pushing the Zotac GTX580 well beyond 30000 P-Score. Impressive indeed.

3D Mark 11

The latest of the Futuremark benchmarking applications, 3D Mark 11, really gets a boost from the 32nm 990X, with both stock and overclocked forms ruling the roost quite comprehensively. 2000 X Marks from a single GPU is nothing to be sniffed at.


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Intel Core i7-990X 

Alien vs Predator

Such is the underlying performance of the Core i7-990X that Alien vs Predator has become GPU limited, with both the stock and overclocked 990X giving identical results. Is there a more impressive ability than that of making a factory overclocked GTX580 become the limiting factor in your rig?

Crysis Warhead

Although there are quite large variances in the maximum frame-rates, the 990X manages to keep the average frame-rate very high indeed. Although the performance of the 2600K cannot be overlooked as it keeps up with the X58s finest.

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Intel Core i7-990X 


Summing up something like the Core i7-990X is one of the easier tasks.

For most of us it's simply a matter of cost, and like all "top range" Intel CPUs it is prohibitively expensive especially when compared to similar models such as the 970, or it's older sibling the 980X.

Those who must absolutely have the best, who demand the highest possible performance regardless of cost, wont mind a jot that you can purchase a relatively close performing full system for the price of this little piece of silicon.

And that is really what the 990X boils down to. For the average user, it's lovely to see a true dream processor that's just way too expensive. For those who demand ultimate performance it's as good as you can get and damn the cost.

For us, it's nice to see the LGA1366 X58 get the send off it deserves. It's still the ultimate enthusiast board, capable of delivering hours of tweaking enjoyment and the biggest possible results no matter what test you throw at it.

The 990X also takes the crown of the highest overclock we have ever achieved in a review on air cooling, all of this was all at relatively safe voltages. We feel that with some sub ambient cooling we could easily push this chip further and have plans to do exactly this very soon.

To look at the price/performance ratio is missing the point. This isn't a mass-market processor. It's not about having something that will survive forever, although it certainly wont be overwhelmed by anything we can think of, it's just a fitting tribute to the series that managed to replace the insanely popular 775 series and bring quad-cores to the masses.

If the performance of the 2600K in certain situations is anything to go by, just imagine what the Socket 2011 will bring to the table. A combination of the P67 tricks and tweaks with the sheer grunt of the X58s.

We're drooling already. It seems that the 990X might not be quite the final big 1366 release, we will have to see if the 995X does get its release in Q2 2011 as yet no one in any official capacity will confirm but the net is a wash with rumors. Only time will tell. As ever the team at OC3D will be ready and waiting if it does!


Thanks to Intel for supplying the Core i7-990X for review. Discuss in our forums.