External GPUs Revisited: i7-8550U + GTX 1080 = Less CPU Bottlenecking?
External GPUs Revisited: i7-8550U + GTX 1080 = Less CPU Bottlenecking?
2018-02-13
man it is super windy here today I can
definitely hear the wind sounds in here
hopefully it's not too bad for you guys
let's get right into it welcome back to
hardware on boxed external GPUs is
something I touched on briefly last year
when I looked at the Auris gtx 1070
gaming box when attached to a cable a
power ultra portable in this video and
perhaps a couple more over the next few
weeks i wanted to revisit a GPUs and
determine whether the latest laptop CPU
hardware from intel solve some of the
problems we saw with the cable a can a
GPU pairing last year so as a quick
recap last time I tested the gtx 1070
gaming box attached to all the Novo
ThinkPad x1 carbon / Thunderbolt 3 the
gaming box does contain a fully fledged
desktop GTX 780 PU but the weak core i5
7200 year with just 2 cores and 4
threads presented a bit of a bottleneck
in a number of games the a GPU did
transform the ThinkPad from a sleek
ultra portable into a genuine
gaming machine with decent enough
performance but the full power of the
gtx 1070 wasn't unleashed by any stretch
in fact the GTX 970 GPU + ultrabook
combo was typically 30 to 50 percent
slower than an actual gtx 1070 gaming
laptop and could be up to 65 percent
slower and really sleepier limited
titles stuttering was also noticeable
issue in some but not all games I tested
with which contributed to week 1% low
frame rates in most games when comparing
these crucial 1 percent low results the
GTX 10 7 EGP is actually a fair bit
slower than a GTX 1060 gaming laptop
again a lot of this came down to the
hard CPU bottleneck and also the
bandwidth limitations of thunderbolt 3
so in this a GPU revisit of sorts I'm
continuing my quest to find the ultimate
portable gaming setup and upping the
ante in several regards firstly gigabyte
kindly swapped out our gtx 1070 gaming
box for their newer and faster GT X 1080
gaming box these even GPUs come with a
graphic card installed and is supposed
to retail for
around 700 us though you know with the
current GPS shortage and price hikes
these boxes are pretty rare but
hopefully at some point soon everything
will calm down this sort of boxes will
become more available the GTX ternary
gaming box it is pretty similar to the
gtx 1070 more in verse regards so i'm
not going to talk about the design build
much because it's basically the same as
what i discussed in my 1070 gaming box
review the key things to note is it's
the same extremely compact size and it's
still plug-and-play / Thunderbolt 3 and
will charge your laptop in the process
provided it supports USB power delivery
secondly and most importantly I'm
testing with new ultra portables that
use Intel's 8th gen cable ayk refresh
CPUs with 4 cores 8 threads and a more
than 50 percent performance leap over
the previous generation there's hope
that the new CPUs in these laptops will
help deal with the CPU bottleneck we
originally experienced so the laptops
are used are the HP Spectre x-360 and
the razor blade stealth both of which
used the core i7
8550 you the most commonly used high-end
8th gen laptop CPU both have full ends
of PCIe / Thunderbolt 3 unlike some
laptops that have just two lanes and
both have 16 gig of ram the spectre x360
is configured to use the default 15 watt
TDP for this CPU and is a bit thermally
constrained at times you'd say the razor
blade stealth is also a 15 watt laptop
it manages to sustain better clock
speeds around 200 to 300 million it's
higher across the board also it's
important to point out I tested
everything using an external 1080p
display hooked up to the GPU display
outputs on the GTX 1080
performance is noticeably reduced when
sending the display signal back to the
laptops display and I wanted to avoid
any such slowdowns also I recommend
anyone using the external GPU to use an
external display for this reason so
let's get to the results starting with
grand theft auto 5 this is a game that
played reasonably well with the old AGP
you set up achieving
36 FPS in 1% lows however the faster GPU
and CPU with this new set up does help
out here average frame rates up by 23%
but crucially 1% loads have improved by
38% the performance doesn't matter
ajit X 1080 gaming system here though we
are getting 1070 max-q like frame rates
we have intestinal lock with Batman
Arkham Knight but it's back for this
round of testing the old a GPU setup
couldn't run the game maximum detail
levels however we are now seeing those
1% lows for above 30fps again 1% low
performance from this ultraportable plus
a GPU combo is around the level of the
1017 max Q rise of the Tomb Raider is a
punishing game at its maximum detail
levels but again we see this new DG /
you take it to a playable level where
previously 1% lawyers with sub 20 fps
performative is actually really good
from this heavily GP eliminated game
essentially matching the gtx 1080 max q
if a little bit slower Deus Ex mankind
divided is a rare title that doesn't
benefit significantly from the extra CPU
or GPU power while average frame rates
do improve by 22%
1% lowest jump up by just 10% which
leads performance between the 1060 &
1070 max Q a bit of a disappointing
result for the a GPU combo in this title
the next couple of games are heavily
demanding on the CPU so they could be
quite interesting
hitman benefits strongly from the
quad-core power of the core i7 8550 you
pushing 50% more frames than the older a
GPU combo looking at the one percent low
results the CPU limitation still gives
proper gaming laptops a significant
advantage the gtx 1060 for example pulls
ahead in 1% Louis despite falling behind
in average frame rates however this
combo does make the game playable at max
settings for the first time civilization
6 sees gains of more than 50% in both
average and 1% lower frame rates thanks
to the faster CPU bringing the 1 percent
low frame rate above 30 FPS for the
first time again performance isn't quite
as good as some gtx 1060 laptops we've
tested but it's still very playable
watchdogs - it's a visually beautiful
game but like a lot of Ubisoft games it
tends to push the CPU and GPU very hard
here where once again see a 50%
improvement to 1% low frame rates and
these frame rates push above 30 fps
just for the first time still we are
limited to around GTX 1060 performance
here
Mass Effect Andromeda runs really well
on the GTX 1080 plus I 78552 combo
doubling the one percent lower frame
rate we saw last time with the older age
APA combo this allows the system to
outperform the GTX 1017 max Q by a good
15 percent though it can't raked the
1080 max Q pray is one of the best
performing games on gaming laptops but
it does struggle massively with a 15
watt CPUs were used with the a GPU here
while one percent low frame rates again
are almost double what we achieved with
the older AGP combo performance is still
below the level of a GTX 1060 which is
typical of the more CPU limited titles
we've tested so far Middle Earth shadow
of war is the final game we'll be
looking at today and this game did come
out after we tested the older AGP combo
so unfortunately don't have data for
that system what I can tell you is the
GTX 1080 eg pew plus I 78550 you record
similar performance to the GTX 1017 max
Q and delivers perfectly playable
performance at 1080p with the ultra
quality preset overall results are very
interesting for this new a GPU plus
ultra portable combination with the GTX
1080 and Core i7
8550 you in hand across the games we
tested there was a 61 percent
performance improvement on average
compared to the GTX 1070 and Core i5
7200 u combo we looked at earlier a lot
of games that were previously unplayable
at maximum settings are now playable
plus stuttering was less of an issue as
evidenced by far more tiles with 1%
lowers above 30fps this is also a much
larger gain that would normally see when
comparing the GTX 1080 and gtx 1070 with
a typical desktop or laptop system with
the same cpu the gtx 1080 is only 20 to
30 percent faster than gtx 1070 but here
we're seeing more like a 60 percent gain
on average it's quite clear that the
additional cpu power helps to improve
performance in a significant way and
those with older Jukka laptops won't
necessarily be able to achieve large
performance gains simply by pumping in
more GPU power while results are really
good for the most part in every game we
tested with is very playable at high
quality settings at 1080p or even higher
resolutions we still aren't seeing the
full power of the GTX 1080 unleashed
with this a GPU set up and there's a
couple of reasons for this firstly the
15 watt core i7 a 550 u is still
relatively weak among faster 45 watt
gaming laptops and of course even more
powerful desktop CPUs the move from 2 to
4 cores at 15 watts does alleviate some
of the cpu bottleneck enough to see
great performance gains but the sort of
ultra portable + e GPU setups are
unfortunately still CPU bottleneck for
the most part and secondly the
Thunderbolt 3 interface still doesn't
deliver quite enough bandwidth to the
GPU even with a full length under
walkthrough so providing pcie 3.0 x 4
stuttering is present in some games that
can't be attributed to extreme CPU loads
or memory allocation issues granted the
number of games that stutter is less
with the faster ultra portable CPU but a
game like The Witcher 3 which we tested
with last time still experiences
performance hitches when the CPU is only
at 60% load and memory allocation is
well below the limits of the system it
is possible that this is a latency issue
rather than a bandwidth issue though
either way I'm confident it's related to
the Thunderbolt 3 interface which makes
it a hard problem to solve by simply
throwing in more CPU power the end
result is the GTX 1080 gaming box hooked
up to a core i7
8550 laptop provides performance most
similar to a gtx 1070 max-q particularly
in more GPU heavy games across the tiles
we tested the e GPU combo was 4% slower
than a gtx 1070 max-q laptop with the
core i7 7700 HQ inside it's also 7%
faster than a gtx 1060 laptop on average
which is great news for 1080p gaming
however the GTX 1080 a GPU paid with the
current gen 15 watt CPU ends up 24%
slower on average there
the GTX teri max-q and that's not even a
fully-fledged GTX 1080 so if you're
thinking of buying the GTX 980 gaming
box or a similar a GPU to used with an
ultra portable laptop don't expect to
get gtx 1080 performance instead you'll
be throwing a lot of extra GPU power at
what is essentially a CPU limited system
don't let the performance difference
take away from what is still a great
setup for gaming though thanks to
external GPUs you can carry around a
feeling like gaming laptop for
productivity on the go then return home
to a desk where you just plug in one
cable to unleash very respectable gaming
performance you know gtx 1070 max-q
performance is certainly no slouch it's
not as good as a proper gaming laptop or
desktop just yet but there's a bright
future for this sort of technology and
some of the early issues get ironed out
I do have a couple of other a GPU gaming
test coming up so stay tuned for those
and a big shout-out to gigabyte for
sending over the GTX to a gaming box so
guys is taking song for us to look at
this in depth but I do think EG appears
are a really interesting product segment
right now anyway that's enough I hope
the wind noise wasn't too bad and I'll
catch you next time
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