Core i7 3960X & MSI X79A-GD65 Review

Hey everybody and welcome to our Intel Core i7-3960X (Sandy Bridge-E) and X79 platform preview. A rather uncommon and slightly unexpected article to write alright, as the architecture behind both, the X79 chipset and the Sandy Bridge-E processors really (initially) were intended for the server platform, but somehow its finding its way towards the consumer channel.

Intel launched the P67/Z68 chipsets and accompanying four core Sandy Bridge processors like the Core i5 2500, Core i7 2600 and recently released Core i7 2700 as mainstream products. That means that the enthusiast segment has a gap that needs to be filled as an X58 with a Gulftown processor like the 980X/990X is already two-three years old. It's exactly there where Sandy Bridge-E and X79 comes into play.

The actual release of Sandy Bridge-E is somewhat peculiar to market... but with a thirst for high-end all manufacturers designed and then redesigned a series of new motherboards that will blow you off your socks.

The biggest competitor for Sandy-Bridge-E, believe it or not, is the X58 platform released in 2008, pop a nice Core i7 980X/990X on there and the raw performance is still fantastic. In retrospect as such one could say that X58/980X (Gulftown) and Z68/2600K (Sandy Bridge) have been products that might have been a little too good.

Today however, we have an article covering the Intel Core i7-3960X (Sandy Bridge-E) and X79 based motherboard. An update to the true high-end six-core processor series aimed at consumers. A processor based on 32nm technology that comes with most of the bells and whistles we have learned to like and love of the current Sandy Bridge processor generation.

Three processors will be released; two Sandy Bridge-E CPUs will have six cores, one model has four cores, hyper-threaded to either eight or twelve threads, the AVX instruction set is here and all processors have a steep but fair 130W TDP. Then there's of course that overclocking potential that the 1st generation Sandy Bridge processors offered, it alone could make this platform downright impressive if that gets your freak on.

Impressive yes, but sure there are obstacles as well, the processor needs a new motherboard as it comes on a new processor socket, LGA 2011. That means reinvesting in a new high-end motherboard probably costing say 200~300 EUR, and then investing in a new Sandy-Bridge-E processor which is probably going to cost you a steep 900~1000 EUR for the most high-end model (which we will test today).

Before we dive into the article, let me make you aware of the fact that we test with a final sample X79 motherboard from MSI. This article will also review the MSI X79A-GD65 8D. Next to that the fellas from G.Skill provided a Sandy-Bridge-E quad channel memory kit, that blew us off our feet. 16GB G.Skill RipjawsZ series memory that with the flick of a BIOS setting to XMP runs stable at 2133 MHz -- in quad channel.

Anyway, head on over to the next page where we'll discuss Sandy-Bridge-E processors, the respective models. We'll also have a chat about MSI's X79 motherboard and chipset and then will throw a decent photo-shoot and a benchmark suite at the products and get an indication what performance is like with the Intel Core i7-3960X (Sandy Bridge-E) and X79 Platform.

Next page please, and please do enjoy.

Sandy Bridge-E

In the weeks to come you are going to hear a lot about Sandy Bridge-E, it's the all new 'enhanced' slash 'enthusiast' version of what pretty much is the Sandy Bridge (Core i7 2600K) architecture, yet with some new features added and some others stripped away.

Simply put, you take all the good ingredients from Sandy Bridge, preferably add two more cores, a slightly increased L3 cache and add a pinch of quad-channel memory. There is one exception to the rule, one Core i7 Sandy Bridge-E CPU that will remain a quad-core processor.

There's also something else missing, though we doubt a little that you'd miss it in this enthusiast grade segment. A change in the architecture is that Sandy Bridge-E doesn’t have an on-die graphics processor built into the architecture. So if you are dependant on QuickSync as a feature then please stick to a 1st generation Sandy Bridge 2300/2400/2500/2600 series processor.

Now if you look at the die for a second with me, do you noitice it as well ? Yep, it seems that the new architecure is in fact an 8-core design with two cores disabled.

Intel will have a lot of flexibility in their hands alright. In this first wave Intel is going to release three Sandy Bridge-E class processors, namely the Core i7-3960X, the Core i7-3930K, and the Core i7-3820. Each will have different clock frequencies and a slightly changed L3 cache. The Core i7-3820 is a quad core processor, the other two are six-core processors.

Below, an overview of the main specs.

Processor	Base Clock	Max. Turbo Clock	Cores / Threads	L1 Cache	L2 Cache	L3 Cache	Memory	Interface	TDP
Core i7-3960X	3.3 GHz	3.9 GHz	6/12	64KB x6	256KB x6	15 MB	Quad-channel DDR3-1600	LGA 2011	130 W
Core i7-3930K	3.2 GHz	3.8 GHz	6/12	64KB x6	256KB x6	12 MB	Quad-channel DDR3-1600	LGA 2011	130 W
Core i7-3820	3.6 GHz	3.9 GHz	4/8	64KB x4	256KB x4	10 MB	Quad-channel DDR3-1600	LGA 2011	130 W
Core i7-2600K	3.4 GHz	3.8 GHz	4/8	64KB x4	256KB x4	8 MB	Dual-channel DDR3-1333	LGA 1155	95 W

What's interesting from a naming point of view is that Intel chooses three different suffixes for the processors, we have an X model, a K model and a 'normal' model. A little confusing, but it does make some sense:

• The “X” suffix is Intel’s Extreme Edition processors, this means the top-of-the-line unlocked processors.
• The “K” suffix denotes a slightly lower end processor yet with its multiplier unlocked.
• And the normal editions are pretty much mainstream without any enthusiast grade overclock options, meaning a locked multiplier.

Cache wise the L1 and L2 caches are 100% similar to Sandy Bridge:

• 32KB data and a 32KB instruction L1 cache per physical core.
• 256KB L2 cache per core.

The L3 cache then, Sandy Bridge has one 2 MB slice of L3 cache per core, that's 8 MB for say the 2600K processor. The Core i7-3960X tested in this article has 15MB of L3 cache, meaning 2.5 MB per core (it's a single block of cache as it's shared).

All three processors will have a 130W TDP, quite similar to the original six-core Gulftown based Core i7 980X. We had hoped to see a lower TDP with the original Sandy Bridge processors being so energy efficient.

 

Quad-channel memory

One of the hip features of the X79 / SBE platform is quad-channel memory. Make no mistake, back in 2008 we already discovered (and reported) in whitepapers that the Nehalem architecture was quad-channel ready, they just never implemented it. But with triple-channel performance as good as it is, that was wishful thinking anyway.

Though nothing has been as rock solid as Intel's 64-bit memory controllers a lot certainly happened. Over the space of three years we went from dual-channel towards triple-channel on X58 (Gulftown), then back to dual-channel with the Sandy Bridge architecture and now with Sandy Bridge-E we see quad-channel memory support. Regardless of what you think about it, progress is obviously always a good thing.

Admittedly, the Intel memory controller, whatever platform you choose, is excellent. Sandy Bridge and its dual-channel controller hauls ass, make no mistake there. At launch quad-channel 1600 MHz low-voltage DDR3 is supported out of the box, and that means an increase from 25.6 GB/s to 51.2 GB/s of available memory bandwidth. That's fast enough to drive a mid-range graphics card ported through system memory fairly well, well if we exclude latency of course.

Quad-channel is going to be crazy stuff, crazy numbers is what you'll see. What the effect will be on real-world performance, well yes... that's trivial at best.

More PCIe lanes

The one thing that people grumble about the most with P67/Z68 is the relatively small number of available PCIe lanes (16) for graphics cards. If you are using a setup with two or more graphics cards (SLI/Crossfire), the PCIe bandwidth is limited at x8:x8.
Here again the performance difference is trivial as running today's fastest cards barely utilizes all that bandwidth, but two x16 and then room for another x8 obviously is much better.

Sandy Bridge-E has a nice 40 lanes available. You can split them up in a variety of combinations, two x16 links with one x8 link, one x16 link and three x8 links, or one x16 link, two x8 links, and two x4 links. So this will be one concern less, though I betcha some of you would like to see three x16 as an option.

PCIe gen 3.0

What should be a prominent feature of the X79 chipset update is the inclusion of PCI Express Gen 3. In a nutshell, PCI Express Gen 3 provides a 2X faster transfer rate than the previous generation, this delivers capabilities for next generation extreme gaming solutions.

Right now we are still disputing the fact that PCIe Gen 3 is working properly, we hear the same thing from several manufacturers. However, with no Gen 3 video cards at hand it is impossible to test and check. If it doesn't work then it might get fixed/enabled with future BIOS updates or... Intel might have scrapped it from the feature list and is bringing it as a feature to Ivy Bridge. For now, however, this remains unconfirmed.

Regardless, we love to explain stuff; PCI Express Gen 3 has twice the available bandwidth, 32GB/s, improved efficiency and compatibility and as such it will offer better performance for current and next gen PCI Express cards. Going from PCIe Gen 2 to Gen 3 doubles the bandwidth available to the add-on cards installed, from 500MB/s per lane to 1GB/s per lane.

So a Gen 3 PCI Express x16 slot is capable of offering 16GB/s (or 128Gbit/s) of bandwidth in each direction. That results in 32GB/sec bi-directional bandwidth.

Again, the big problem is that to date there really is nothing here in the lab we can use to test these new slots. You need proper compatible hardware, like this platform, but also a graphics card or say PCIe SSD supporting the new standard.

LGA 2011

It is a little unfortunate that once again we see a new socket with this processor series. Over the last three years we left LGA 775 then started with LGA 1366, then moved to LGA 1156, with Sandy Bridge we moved to LGA 1155 and now we have to harbor the processor in socket LGA 2011.

We know, it's unfortunate, but with a changed architecture and features like the quad-channel memory controller, the lack of an embedded graphics unit and the massive update towards 40 PCIe lanes the entire dynamic changed. So ever since 2008 that's four different CPU sockets in the consumer market.

It's not a weird move to make, but for those on LGA 1155 hoping to upgrade to Sandy Bridge-E on the same motherboard, well it's not a possibility.

So yes, this means that for a Sandy Bridge-E processor you'll need to purchase an accompanying motherboard based on the X79 chipset. Not just that though, the cooler mounting is completely different as well, you'll need to seek a new mounting bracket for your cooler, or purchase an LGA 2011 compatible cooler.

An Optional Liquid CPU Cooler

Next to AMD Intel has plans to sell special kits of the high-performance Sandy Bridge-E processors that in addition of the CPU will also include an Intel branded closed loop liquid cooler. This is the first time that the chip maker will bundle any of its processors with a water cooling solution.

In addition to selling the liquid cooler as part of a kit, Intel also plans to release this solution separately. The CPU water cooler is made and built together with Asetek, a maker well renowned for its high-quality closed loop liquid coolers, and includes a water block and pump assembly that goes on top of the CPU and a 120mm radiator with a pre-fitted fan.

Both the pump and the fan were designed to feature blue illumination, which closely resembles the color of the Intel logo. The Intel branded Liquid Cooling Solution can be found under SKU code RTS2011LC.

 

The X79 chipset

Sandy Bridge-E needs a new accompanying chipset, X79 is what it's called. For those that are wondering, the internal codename for this chipset is Patsburg (Patsburg-X I think more specifically). Compared to X58 with a Gulftown processor there are obviously significant changes, since the Northbridge is housed inside the actual processor these days. That means that Sandy Bridge-E will connect directly to the X79 Express chipset through the DMI interconnect.

X79 Express chipset has been the topic of much discussion over the months as specs simply did not seem to finalize. Fact remains that it seems the chipset has been downgraded. Two of the changes might explain what we told you earlier, we think the PCI Express 3.0 storage uplink to the CPU was canceled out and Intel decided to cut out four SATA/SAS 6Gbps ports. And that brings us to a chipset that resembles P67 very much.

In the end you will only get two SATA 6 Gb/s ports and four SATA 3 Gb/s ports supported natively by the chipset. So that is six in total for which you may configure RAID 0, 1, 5, 10 if that pleases you.

Motherboard manufacturers can, and likely will add Marvell, ASmedia and JMicron controllers to get that number up as for the most high-end chipset this seems a little too 'mainstream'.

USB ports then; this is just weird, the chipset only supports USB 2.0, not 3.0. A choice we do not understand for Intel's best offering anno 2011. You get 14 ports made available to you. USB 3.0 support once again will need to come from 3rd party controllers with extra core logic and thus overall costs mounted onto the motherboard.

Overclocking Sandy Bridge-E

Good news for Sandy Bridge-E based platforms is overclockability. The original Sandy Bridge processors at the default baseclock (BLCK) were rather horrible to overclock. It has a lot to do with how the processor deals with the embedded graphics subsystem. If you were lucky you'd be able to increase the baseclock maybe 5 to 10 MHz multiplied at best. This is why the K and now X model processors have been introduced, easy overclocking by increasing the multiplier up-to a multiplier of 57.

This feature of course remains the same for Sandy Bridge-E with the X (Extreme) and K models. However, you should be able to overclock on the baseclock a little better now as well thanks to a new buffer chip that allows for 33 MHz increments.

Meanwhile we'll all still overclock based on the multiplier as it is 10x more easy and efficient to do so. We have limited overclockability for this review, as we are using an engineering sample motherboard that is not yet finalized. But even with that in mind it did not stop us from trying. We'll show you the overclocked results throughout the article. Regardless, the results will be flabbergasting.

Power Consumption

Here's where we'll slowly move into physically testing the processors and respective chipsets.

The new Sandy Bridge E based processors are a bit of a redesign alright and as a result they are quite energy needy processors with a 130W TDP. What you'll notice a lot, is that in idle these things kick ass in matters of power consumption, whereas at peak TDP they behave quite normally.

In an IDLE state the PC (X79 / 3960X / 16GB memory / GeForce GTX 580 / SSD) consumes 86 Watts. Mind you that we measure the ENTIRE PC, not just the processor's power consumption.

When we place load on the CPU and we see the power draw rise, the system now consumes roughly 201 Watts. This is with merely an SSD, memory and the GTX580 installed. Your average PC will draw a little more power if you add optical drives, HDDs, soundcards etc.

Overclocked power consumption by added voltage ... um yeah well we'll discuss that on the next pages ok?

I want to make it very clear that power consumption measurements will differ per PC and setup. Your attached components use power but your motherboard can also have additional ICs installed like an audio controller, LUCID chips, network controllers, extra SATA controllers, extra USB controllers, and so on. These parts all consume power, so this is an indication.

Next to that, we stress all CPU cores 100% and thus show a PEAK power consumption. Unless you transcode video with the right software your overall/average power consumption will be much lower.

Overclocking - the Core i7-3960X on MSI X79

Meet the spaghetti of wires, this was the initial engineering board by the way, where we used Corsair DIMMS.  In our actual review later on you are going to notice how freaking much more performance the overclock delivers. I mean really, it's even a little crazy to observe. In today's article we'll stick to that 3DMark overclocking session with the MARS II. Have a peek:

Now we tested the ASUS Mars II on a Core i7 980X (3800 MHz), that gave us 11000 points in the P score. By just switching to the Core i7-3960X / X79 platform we gain roughly 500 points.

However when the Core i7-3960X is overclocked to 5 GHz, we are nearing 12000 points already. 3DMark is massively GPU dependant though, let's take 3DMark Vantage from which we all know loves multi-GPU setups in combo with fast processors.

3DMark Vantage then. So again the same thesis, the ASUS Mars II on a Core i7 980X (3800 MHz) scores 33819 points. And on the Core i7-3960X / X79 platform we close in at nearly 40K points.

Once we overclock the Core i7-3960X to 5 GHz, we get 47K points (P mode) already. Coming from a Core i7 980X (3800 MHz) with its 33819 points, the difference obviously is gigantic. Look at that CPU score for a second, and yes, PHYSX is disabled and running over the CPU not the GPU, before anyone starts to wonder.

What's quite shocking is the combination of it all, the CPU overclock at 5 GHz and the dual-GPU based Mars II are drawing up-to 741 Watts. Wowzers. In a default setup these numbers are very decent by the way -- let me clearly state that.

Final words and conclusion

Blimey, the Sandy Bridge-E platform is a power-house and it is bound to set some new records.

I'll start off the conclusion a bit weird though; in contrast to say Z68 and a Core i7 2600K processor, I'll probably hesitate a little to really recommend Sandy Bridge-E unless you really need it. See, it will require a new, very expensive, motherboard and a new processor for which the top model is gonna cost you 950 EUR / 990 USD. The 3930K is going to cost you 500 EUR / 555 USD. You can purchase the processors seprately, and if you are looking for the Liquid Cooling solution as well you must add another 85 to 100 USD.

So that difference might be a little too much versus what you gain features and performance wise.

However, have to acknowledge that Intel's six-core processors are as fast as a lightning strike (in a very positive way of course), it's just seriously fast stuff. Here again though I do need to note down that it's nothing out of the ordinary compared to say a Core i7 980X/990X at baseline performance (not overclocked).

But ... the dynamic changes fast once you start to overclock though, as that 5 GHz, it took merely a few minutes to set up, verify and monitor. The potential there is just much better than Gulftown based processors.

Somewhat of a worry is X79, we definitely do like the extra PCIe lanes, yet we are still puzzled about PCIe Gen 3 compatibility. We know the motherboards support it, yet the processors remain an unknown, and yeah ... it does double up on bandwidth once it kicks in. Let's just hope it will get supported with the final launch.

Per core performance is really nice, the Turbo kicks in nicely. So for the professional user who uses heavily threaded software like content creation, that's where Sandy Bridge-E will make a difference. Add to that Quad-channel memory with near silly bandwidth and plenty of PCIe lanes and you'll have a platform that will be hard to beat.

The Intel X79 chipset is by all means sufficient, but just that. We expected more, PCIe gen 3, SATA3 ports and native USB 3.0 amongst others. Luckily the manufacturers will adapt and react to that, the MSI X79A-GD65 motherboard used in today's review offers everything you wish and much more. However, the minute the manufacturers have to add ICs and compensate for the chipset, the more components are used driving prices upwards -- and that will make a Sandy Bridge-E PC very expensive.

The regular 4 DIMM GD65 will cost you 279 USD whilst the eight DIMM version will cost 299 USD in retail. We expect EURO prices to be slightly lower though.

Sandy Bridge-E however seems to be a ridiculously fast platform. MSI's X79A-GD65 motherboard was working fantastic, even when we popped in the GSKILL RipjawsZ 2133MHz quad channel memory, all we did was flick a BIOS XMP switch and boom, it was working 100%. The platform as tested comes with additional controllers, a plethora of them. So you will gain USB 3.0, SATA3 options and little extras like the quality component selection, overclock tools and implementation at hand.

That said, the Sandy Bridge-E performance is impressive, but not that different to X58/Gulftown if you leave overclocking out of the equation. If you are the proud owner of a P67/Z68 and a Core i7 2600K, you really probably will not miss out on much either, unless you really need two more cores of course.

In closing, though untested we think that the Core i7-3930K will be the most interesting product in terms of price versus tweaking. Exciting times are ahead of us. Remember though, Sandy Bridge-E is looking to be merely a half way station in-between Sandy Bridge and Ivy Bridge. But take it from this editor, if you leave out pricing then from A to Z it was a brilliant experience testing and tweaking this platform. And that's really what high-end gear is all about.