nvidia's original g-sync technology has
largely kept the promises that it made five years ago of eliminating tearing
input lag and stutter in high-end gaming displays
but the how of this technology is something that they've kept under wraps
until now
which is what makes today's video really really special because nvidia sponsored
our trip down to santa clara today where we will be the first
non-nvidia personnel to ever see one of
their g-sync optical labs so let's go find out how you make a gaming monitor
shall we
now nvidia doesn't actually manufacture display panels that work is best left to
the experts at samsung lg display
au optronics and the like but inside this cage come on get around
here behind me is a sample of every g-sync monitor that
has ever been built and the thing is
there's far more to creating a great
finished gaming display than just taking whatever panel those guys hand you
slapping it into an enclosure and calling it a day
in fact while the situation has improved a lot especially on the desktop
nvidia still fails over 50 percent
of the laptop displays that get sent to them for validation
so each one of these assuming that they don't immediately
fail the more basic checks will get subjected to over
300 tests some of which take hours or
even multiple days to run
so i feel kind of bad for the techs who drew the short straw for our visit today
and had to shut down you see the issue and actually the reason that the walls
are all painted black in here is that with our filming lights on they can't
run any real tests because the results will be invalid so we're gonna try to
get out of their way real quick here on this bench then is our first real
test here so it's a pretty simple one on the surface
but it's one that will weed out a surprising number of variable refresh
rate displays so our gpu here runs a
benchmark with extreme swings in the frame rate which is designed to expose
weaknesses in the t-con or timing
controller which is the part of the panel that takes the output from the
scalar and translates it into something that the actual drivers of the tft
matrix can understand now the results of these failures are usually quite obvious
because if a t-con experiences a firmware problem for example causing an
overflow condition its go-to emergency
response is generally to blank out parts
of the panel or even the entire thing temporarily to prevent it from being
damaged apparently they actually had one of those come through here just the
other day but that doesn't mean that running these
tests is simple for one thing these
kinds of problems can be weird edge cases i mean that's why the manufacturer
didn't notice them so they can take a long time to manifest which is why they
run for up to 48 hours before assigning
a pass and for another just hooking a source up to a bare
notebook lcd is an ordeal and a half
so of course you need a mobile gpu in
order to validate mobile displays but using a standard desktop test bench
would save you a lot of time so check out this frankenstein creation i've
actually got another one right here so this according to the folks here
is a touring mobile gpu but soldered
onto a development board with just like
this cooler just plugs straight into 12 volt power
it just runs at full speed all the time that's why these things are so loud and
then it's just bristling with diagnostic
readouts and and uh sort of measurement
points and then there's then there's the really cool stuff so this right here
is our dvi output or something that's on a
daughter board for some reason and on the back here this is really cool
so these interfaces back here are designed for all of the different
implementations of embedded displayport
that you might see from the various panel manufacturers
so they make their own daughterboard pcbs here so they can adapt this weird
development card to run any display that they want on to our next test though one
of the hardest parts of creating a variable refresh rate display is
preventing flickering but the thing is not everyone perceives flicker the same
and even if a flicker isn't visible to the eye it can still cause fatigue and
headaches so that is where this test comes in
now it doesn't look like much but the lab techs here can change this boring
gray screen to output any refresh rate they want then they use this klein
instrument's k10a a basic luminance meter to measure the amplitude and
decibels of any changes in the output
brightness then that is of course assuming that the panel makes it this
far they use this special box of nvidia's own creation to
kind of like a like a doctor checking your like heartbeat or something check
all the different areas of the panel to see which one is the worst and then
ensure that even that is still within spec rounding out panel selection is a
whole battery of other tests color reproduction color gamut absolute
luminance native contrast ratio pixel response times you pretty much name it
then we can move into this room once a panel is validated it can move on to
stage two actual display development at this point
things get a lot pickier so this forty
to fifty thousand dollar xy positioning jib is precise to one tenth of a
millimeter so what they do is they light up the display so the one that we're
looking at right here is a g-sync ultimate unit with hdr 10 support at up
to 1 000 nits peak brightness and then they take measurements across the entire
surface to ensure that it's uniform it's pretty freaking intense except
that is just scratching the surface so
this display also features 384 zone full array backlighting and
handling that evenly is really freaking tricky in this test
nvidia is evaluating each of the individual leds that makes up the
backlight array not just off and at full force but at its various
steps in between because you guys gotta understand they need to account not just
for the drive level of each one of these zones but even the neighboring light
lead from other zones around them and then making matters worse the whole
thing has got to work perfectly at every brightness level and every refresh rate
so then once the luminance behavior of the panel
is characterized it's either fantastic out of the box ready to go
or much more likely it needs some work it's
no bloody wonder that these 4k 144hz hdr
displays got delayed right speaking of delays in this room
also uh professionally darkened out don't you love it when like
an engineer is given a problem and told to solve it quickly i love this um
anyway in here is one of nvidia's bfgd or big format
gaming displays now the process you're seeing here is
nothing special if you've ever professionally calibrated a display before basically a signal generator so
this laptop outputs a known value let's say white or other more different white
or red or something and then a sensor like this spectroradiometer checks how
close it is to what it's expecting but what's different about nvidia's approach
here is that instead of just calibrating
finished displays during the development process they're
jumping in to make sure that there are no underlying issues with the technology
that are going to crop up while operating in variable refresh rate mode
that can't be corrected because the thing is
many lcd characteristics change when the refresh rate changes another
fun one to deal with is overdrive so overdrive basically works like this
you've got a pixel and you want to take it from
level 100 to level 200 which might take
it let's say 8 milliseconds natively well if that's not good enough for the
performance you want with overdrive we can tell that pixel i want 250. and
because that's a bigger change it's going to reach our actual desired level
of 200 faster so you're basically giving it a bigger kick so you might get there
in just four or six milliseconds
the trick though is to not go too high
or you'll get too high of a value overshooting the intended target
now here's the thing at 60 hertz fixed refresh rate
this is relatively simple so the monitor just has a lookup table built into it of
what it should shoot for in order to have the value be correct by the next
16.6 millisecond refresh cycle
with variable refresh rate well it has
to compensate how much of an extra kick
it's giving according to how much more or how much less time it's going to have
to get to the actual desired value
and even driving the leds in the backlight is a complicated matter so
this is the back of a g-sync ultimate desktop monitor but the internal guts
here are actually fundamentally similar to the bfgd that we just saw so at its
heart is the powerful g-sync processor that
contains much of g-sync's special sauce
then around it is kind of like the uh
the motherboard of a monitor so
this here is something that the manufacturer of the monitor would
customize depending on what they want for display connectors usb hubs
built-in audio that sort of thing then finally there's a third part here so
these are kind of like the wings that make g-sync hdr fly
so these driver ics right here take a
digital signal from the g-sync module scaler for what the luminance level
should be for each of the 384 leds that make up the backlight here
then they output a given dc voltage to
each of the 16 transistors that drive
the current that actually lights up the individual led in each zone
just the right amount but like hold on hold on a second here
a corsair commander pro can drive dozens of rgb leds per channel
with like four wires what is all of this for well here's the
thing at 144 hertz you've got under
seven milliseconds per frame and you have to both determine and write all 384
of those values each frame and add up to a thousand
nitspeak brightness so this is not a trivial task like man i can imagine the
meeting where they decided to build this thing right now
like all right team so we've never built a tv before
so the plan is to build the most difficult one
lol good luck everyone and break
which leads us finally to certification now the third and final stage might not
be that visually interesting but it's arguably the most important so this is
the point at which nvidia receives the first finished units of each display and
goes through that whole ordeal again to ensure that nothing got lost in
translation and i have to say going behind the scenes today gave me a
much deeper appreciation for what nvidia has been doing in the display industry
the eagle-eyed among you for example might have noticed that one of those
backlight driver boards on this prototype has an nvidia silkscreen on it
while the other one has something else
that's because as part of developing g-sync ultimate nvidia actually created
the reference design for these driver boards since nobody had ever done a
384-zone 27-inch panel before now
unfortunately i wasn't able to show you guys everything that i saw but what i
can say is that my experience today has shown me definitively that this is far
more than just a a rubber stamping
certification fee operation so then there are three tiers of g-sync
now g-sync compatible displays don't go
through anything that you saw today nvidia performs four variable refresh
rate tests to ensure that they're suitable for a basic vrr gaming
experience then there's g-sync and g-sync ultimate where you're getting the
deep collaboration between your graphics card manufacturer and your display maker
with ultimate also including support for hdr gaming which as we've discussed in
the past looks pretty freaking sick
so that's it for today guys massive thank you to you for watching and to
nvidia for sponsoring this video and just straight up allowing us a peek
behind the kimono this was absolutely incredible if this video sucked you guys
know what to do but if it was awesome get subscribed hit the like button or
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should totally join especially if you have any questions about building a
fantastic gaming rig or buying a variable refresh rate monitor or
whatever the case may be