With all that said, let's now look at the results from the Broadwell and Haswell units. Both use the exact same cooling system, from what I could tell looking inside both. The Broadwell technically loses here, by less than 1 percent. But when you remember that the Haswell technically has the higher clock speed, it's actually a win for the Broadwell to be so close.
3DMark Graphics performance
While Intel says Haswell-to-Broadwell performance shows maybe a 5-percent difference on CPU functions, on graphics the company says the spread's more significant. That shows up in 3DMark, where the Broadwell-chipped Dell offers up about 10 percent more graphics performance in Cloudgate. I even saw a 15-percent difference between the two when the graphics load is scaled back further to 3DMark Ice Storm Extreme. Don't fool yourself--you won't be playing Batman: Arkham Knight at 4K with either CPU, nor any recent graphics-intensive game, but a game of Minecraft, Counter Strike or Portal 2 with the settings turned down enough are playable.
My last benchmark chart for the mobile dual-cores is the most important one for the applications in an ultra-portable laptop. Let's be realistic: People aren't encoding 4K video or playing Battlefield 4 on these laptops, they're pushing browsers, Office and maybe Photoshop, or coding on them. All within the performance envelope of a dual-core processor. What people care about most is the battery life.
MobileMark 2014's Office Productivity battery test uses common applications such as Word, Acrobat and Chrome to simulate a day of pushing mundane office tasks while on a battery. The test even lets the laptop go to sleep for a few minutes, when the typical office drone might be checking their phone or chatting to the person in the next airplane seat.
Here we see the 14nm Broadwell CPU pay off very healthy dividends over the 22nm Haswell CPU. Remember, both laptops use the exact same-capacity battery, SSD, OS and just about everything else. For the record, the RAM chips were different, as were the battery makers, but they used the same specifications.
With all things being equal, a 10-percent improvement in battery life is significant when you consider that Haswell was already an outstanding performer. Haswell significantly moved the ball forward over Intel's 3rd-generation Ivy Bridge CPU. Matt Smith actually did a somewhat similar test, pitting an Ivy Bridge laptop against a Haswell laptop. Both laptops were similar, but Haswell CPUs required a wealth of new components such as chipset and voltage changes, so comparisons don't really isolate just the CPU.
I'm fairly certain that if the laptops used here had CPU sockets and I could switch the chips, my results would be the same.
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