Seven $260-$320 X79 Express Motherboards, Reviewed

LGA 2011 Motherboards, Just A Little Cheaper

When Intel launched its Sandy Bridge-E-based processors and platform, the company sampled its $1000 processor exclusively. Certainly the top-end Core i7-3960X is a worthy successor to the Gulftown-based Core i7-990X that it replaces.

As we all know, though, paying a premium to get that flagship part isn't the direction most enthusiasts go. Instead, it's more common to buy down the stack and overclock, extracting real value from less-expensive parts. Last generation, it was common to see power users buying pricey motherboards and affordable Core i7-900-series chips, turning them into 4+ GHz speed demons.

Intel's new high-end platform is no different. The Core i7-3930K is a much more attractive high-performance prospect than the -3960X. And now that we've seen what a -3930K can do, we're ready to have a look at some of the less expensive LGA 2011-based motherboards more appropriate for the second-fastest CPU's more attainable price tag.

As we wait for Intel to push its least-expensive Core i7-3000 CPU into retail, today's round-up sees seven mid-priced motherboards put to the test.

The Trouble With Overclocking

Between the Tom's Hardware editors, we have several Sandy Bridge-E-based chips. Editor-in-chief Chris Angelini has a Core i7-3820, -3930K, and two -3960Xs, Don Woligroski has a Core i7-3960X, and I have three Core i7-3960X processors. Two are C0 processors, but the other represents the retail-class C1 stepping. Naturally, that's the one most representative of what you'll find on shelves.

Unfortunately, not all processors are created equal, even within the same stepping. Furthermore, not all flaws qualify as show-stopping defects. After receiving a second unlocked processor that wouldn't take a manual multiplier adjustment on a majority of motherboards, we contacted the first engineer we could find for a full diagnosis.

Simply increasing the multiplier causes both this C1 processor and Don's to hang while loading Windows 7, even when trying to boot from the Windows 7 DVD. A few changes to the power settings prevents UEFI initialization, and a few additional power management changes sees some motherboards to read the processor at 91° Celsius, the point at which it throttles. On most platforms, the only multiplier range that works starts at the lowest Intel Turbo Boost ratio (36x) and goes downward.

Our friendly engineer then started testing every processor he could get his hands on and noted that around 1 out of 40 C1-stepping samples exhibited the same behavior. Not willing to settle on a single source, we went on to contact the representative of a second motherboard manufacturer and, without reporting the information from the first, were told that approximately 2% of Intel’s retail C1-based processors exhibit the same behavior. Rather than split hairs over the exact number of affected chips, we searched the Internet to find two overclockers who reported the same problem to online forums with their retail builds.

Both of our processors work perfectly at default settings. So, they can't be returned for replacements under warranty, even though their elevated multipliers don't work. One of our CPUs still manages to hit 4.4 GHz using BCLK adjustments. The other stretches as high as 4.7 GHz at 1.35 V. Since the flaw is out there, in the wild, we proceeded with our testing using the better of the two C1-based chips. When necessary, we used the BCLK to hit highest stable frequency on each motherboard.

Now that C2-stepping processors are becoming available, you can look forward to us trying our luck with Intel's new stepping in our next round-up.