Load Delta Power Consumption

Power consumption was tested on the system while in a single MSI GTX 770 Lightning configuration with a wall meter connected to the OCZ 1250W power supply. This power supply is Gold rated, and as I am in the UK on a 230-240 V supply, leads to ~75% efficiency > 50W, and 90%+ efficiency at 250W, suitable for both idle and multi-GPU loading. This method of power reading allows us to compare both the power management of the BIOS and the board's ability to supply components with power under load, and includes typical PSU losses due to efficiency.

Power Delta (Long Idle to OCCT)

Each of the Broadwell-E SKUs are rated at 140W, however they vary between 6 cores and 10 cores and with different frequencies.  Normally one would assume that the core/frequency ratio would be adjusted to match TDP, but ultimately using more cores can consume more power. We see a distinct increase in power consumption moving up the product stack.

Prime95 Core Loading

For this review, we also looked into peak delta power draw when varying the number of cores using Prime95’s mode for peak power consumption. Prime95 identifies cores with multiple threads and adjusts its loading/pinning accordingly.

Prime95 Core Loading

Broadwell-E Overclocking


Our standard overclocking methodology is as follows. We select the automatic overclock options and test for stability with PovRay and OCCT to simulate high-end workloads. These stability tests aim to catch any immediate issues with memory or CPU errors.

For manual overclocks, based on the information gathered from previous testing, we start off at a nominal voltage and CPU multiplier, and the multiplier is increased until the stability tests are failed. The CPU voltage is increased gradually until the stability tests are passed, and the process repeated until the motherboard reduces the multiplier automatically (due to safety protocols) or the CPU temperature reaches a stupidly high level (100ºC+). Our test bed is not in a case, which should push overclocks higher with fresher (cooler) air.

Overclock Results

Due to time constraints we were only able to overclock the i7-6950X using the MSI X99A Gaming Carbon motherboard. MSI has improved its overclocking options as of late on the Z170 platform to make it easier to use, but our BIOS did not have those most recent updates, particularly for load line calibration. However, our sample hit 4.1 GHz at 1.30 volts before the OCCT load temperatures were prohibitive to move up any further. We saw similar things when testing the mainstream Broadwell parts with Iris Pro, which shows that this sort of overclocking performance might be indicative of the silicon itself.

That being said, speaking with our contacts at various motherboard manufacturers, we're told that 4.1 GHz is a reasonably average processor result for Broadwell-E. Some processors will hit 4.3 GHz on air at around the same voltage, whereas others need up to 1.4 volts, and thus results will depend on the cooling setup used or the thermal characteristics of the silicon. I have also been told that AVX is a different story: for any peak frequency attained normally, AVX overclock stable frequencies will be around 200-300 MHz lower.

Gaming, Cont: GRID: Autosport & Shadow of Mordor Catching Up: How Intel Can Re-Align Consumer and HEDT
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  • unityole - Tuesday, May 31, 2016 - link

    well time to read
  • Drumsticks - Tuesday, May 31, 2016 - link

    I've gotten through about half of it so far (and the conclusion) but man, those prices... Zen is supposed to be really, really close to Broadwell in IPC. Imagine that 8-core Zen part with 90-95% of BDW-E performance at 30% of the price. That would be really pretty nice.

    Great review so far, and I'm sure the rest is awesome!
  • SunLord - Tuesday, May 31, 2016 - link

    If Zen is 90% the performance of BDW-E then it will be priced to match that though I doubt they'll break $999. AMD will try and under cut Intel but it's not gonna give a away a great performing chip like it had to with the crappy cores it has now
  • jjj - Tuesday, May 31, 2016 - link

    lol 7$ per mm2 for top SKU is beyond outrageous. Anyone buying this deserves a nomination for the Darwin Awards.
    Zen can compete with Intel's 2 and 4 cores + pointless GPU on price, easily.
  • Railgun - Tuesday, May 31, 2016 - link

    Because dying in a stupid way is akin to buying an expensive chip. And since when would price per area be any useful metric?
  • Shadow7037932 - Tuesday, May 31, 2016 - link

    >Zen can compete with Intel's 2 and 4 cores + pointless GPU on price, easily.

    That's what you're hoping for. For all we know, there could be some serious issues with Zen. Remember the TLB issue with the original Phenoms?
  • silverblue - Tuesday, May 31, 2016 - link

    ...and the AVX memory write performance issues with Piledriver. Still, what architecture doesn't have bugs?
  • Ratman6161 - Tuesday, May 31, 2016 - link

    I've been wanting to like AMD for a long time. I still remember the good old days of the Athlon 64 and 64 x2 when they used to beat Intel and at a lower price. but they keep on disappointing me. I'm taking an "I'll believe it when I see it approach"
  • Azethoth - Tuesday, May 31, 2016 - link

    I think you mean we remember that one time the Athlon 64 beat intel and we bought it but everyone else stuck with Intel because Intel, or AMD is for gamers, or Intel being monopolistic.

    That is more than 10 years ago though and it seems that by stated policy those days are never coming back for AMD.
  • usernametaken76 - Tuesday, May 31, 2016 - link

    Eh, I remember prior to Athlon 64, just plain old Athlon XP, the value was tremendous compared to Intel. There was no sense in buying Intel if you were building a gaming rig, something for yourself to do basic computing tasks, etc. Intel was for suckers who bought business class desktops.

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