APC - September 2015 AU.pdf

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LABS
BENCHMARK RESULTS
CINEBENCH R15
INDEX - SCORE
INTEL CORE I7-5775C 763
INTEL CORE I7-4790K 880
0 200 400 600 800 1000
X264 V4.0
AVERAGE FPS
INTEL CORE I7-5775C 45
INTEL CORE I7-4790K 53
SANDRA BANDWIDTH
GB/S
INTEL CORE I7-5775C 20.1
0 10 20 30 40 50
INTEL CORE I7-4790K 17.7
0 10 20 30 40 50
METRO: LAST LIGHT AVERAGE FPS
INTEL CORE I7-5775C 44
INTEL CORE I7-4790K 52
PEAK POWER
WATTS
INTEL CORE I7-5775C 104
0 10 20 30 40 50
CPU
$569 | WWW.INTEL.COM.AU
INTEL CORE I7-4790K 195
NOTE: ALL GAMES TESTED AT 1080P.
0 40 80 120 160 200
Intel Core i7-5775C
Desktop Broadwell is here. Was it worth the wait?
Intel’s fifth-gen
desktop CPU, the Core
i7-5775C, is finally in
our test benches. So
what is Broadwell? It’s a
14nm production process
die shrink on what’s still
essentially Haswell CPU
tech, giving serious power
efficiency to the chips.
That’s why they’re first and
foremost of interest to the
mobile crew, although they
retain some interest on
the desktop because you
also get the very best in
processor graphics.
This is the first time the
Iris Pro level of graphics has
appeared in socketed form,
and compared with the HD
Graphics 4600 parts in the
latest Haswell Devil’s
Canyon chips, the Iris Pro
6200 has more than twice
the execution units (EUs).
Elsewhere, you’re looking
at classic Core i7 stats – four
cores with eight threads.
Because this a ‘C’ class chip,
you only get a clock speed of
3.3GHz with a max turbo of
3.7GHz, although it retains
unlocked multipliers to aid
overclocking.
Technologically speaking,
the i7-5775C is the top CPU
in Intel’s standard desktop
lineup. For the next few
weeks, anyway. So what
makes it a relevant upgrade
to the cheaper Devil’s
Canyon Core i7?
On the face of it, there
seems to be no reason to
upgrade from your current
Haswell i7, and probably
most existing i5 chips. The
i7-5775C is a good chunk
more expensive than the
i7-4790K, and in terms of
straight clock speed and
thus gaming performance,
it’s a bit of a bust. In our
benchmarks, X264 and
Cinebench gave a landslide
victory to the last-gen CPU.
The bright spot is in the
memory bandwidth figures.
The Broadwell chip shows
big improvements, topping
anything we’ve seen outside
of Ivy Bridge-E processors.
And what of overclocking?
Sadly, we couldn’t hit the
standard 1GHz overclock
that Intel CPUs often offer.
Boosting it from a 3.3GHz
base up to 4.2GHz is no mean
feat and does improve
performance, but nowhere
near enough to worry the
existing top Haswell chip
in straight performance.
But this isn’t where
Broadwell is meant to
compete. It’s a low-power i7
with high-end graphics and
limited overclocking. At
stock speeds, the peak
power we were seeing
during Cinebench tests was
just 104W, with the CPU
only a shade over 50°C. But
even when overclocked to
4.2GHz, the CPU was still
under 60°C and only drew
another 50W at maximum.
That’s some seriously
impressive efficiencies. This
eight-threaded CPU is barely
drawing the same power as
last-gen quad-thread parts.
In terms of its graphics
performance, having more
than twice the EUs of the
Haswell HD Graphics 4600
– 48 compared to 20 – the
Iris Pro 6200 delivers a huge
performance boost. Gaming
at top 1080p settings goes
from practically slideshow
levels to genuinely playable.
As a preview of what we
can expect from the next-
gen Skylake family, this
14nm die shrink is darned
impressive. But the thought
of spending $569 on one
is beyond the pale. Even
with the excellent Iris Pro
graphics finally hitting
socketed CPUs, we struggle
to see who would actually
consider picking one up.
This is a chip that might
have looked impressive last
year, and maybe even today
if it had a higher clock speed
and lower price. But that’s
not the case, so there’s little
reason to consider it.
Dave James
Verdict
Features
Performance
Value
Excellent power efficiency, impressive
low temps and a great CPU graphics
core, but it’s way too expensive.
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