did you know that you can overclock a graphing calculator for fun and profit
yeah so we called up texas instruments and we're like hey guys can you send us
some calculators to overclock so they sent us this one which
this doesn't look like a calculator like it does that looks exactly like a
calculator what are you talking about but it doesn't look like the calculator no it's not the calculator so we
actually had to go digging through
alex's sentimental drawer where we found
the very ti 84 plus that got him most of
the way through engineering school and also most of this job so i guess what
you're trying to say is you'd like for us to not break it yes
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before we go any further we should probably address why anyone would want
to overclock a graphing calculator now one obvious reason is that when you
enter a more complex function in them they can actually take a hot minute to
spit out the results but there are some even more fun and geekier reasons than
that doom playing doom on your calculator in class turns out that's a
thing you can do and the more you overclock it the faster it'll run doy of
course to quantify the benefit of our experiment here we're going to have to
set a baseline so let's get doom installed on this puppy and see how she
runs all right so in order to get programs onto your
calculator you just get ti connect it has not changed since i used in high
school go to send to device all right so
calculator overclocking in here we have doom 2 runs a bit better so let's toss
that on wow the hat animation i remember but the pages and
when you deleted things how the page would just oh my gosh
yeah this is pretty slow to uh render new frames oh i think i got a new
oh pistol bang bang bang bang bang hey back off before he first oh he hit me
yeah these frames render a little on the slow side i can see how this experience
could be enhanced with a faster calculator
that's it eh that's the brain yep we need to find out how much power it's
drawing so that you know you can't design a thermal system
without knowing how much power you're drawing so first thing we need to do is
power it that's flux you're just gonna solder leads to it positive and negative
let's tin some wires here suckas this is nice normally they don't let me
use the soldering iron well oh yeah the soldering that's coming in a bit you are
not doing you can do this one like look at the landing pad you're not doing the harder
ones look at this that i did this morning
that is pretty impressive yeah assuming that it actually still works i have no
clue okay so let's see if i did it right
hey it's live yay
he was a little nervous i saw him okay so i was slightly concerned about this
uh it's drawing so little power that it's not registering on our power supply
here yes so we're gonna have to
calculate it a different way one moment so all we need to do is hook up to our
multimeter which should tell us how much current we're drawing .001
amps can you change the range and see if we can get that a bit more precise
no you know what though i bet what we could
do is actually do something on the calculator so i'm going to take that from you and i'll sanitize my hands
after and then you do something
like run doom for example okay so we're gonna graph now
oh yeah 0.013
is the max 0.091 watts of heat to dissipate
for the total thing including the display so 0.1 watts yeah i think we've
got this and we're taking this one step further
what do you think the temperature is going to be 25 degrees
i was thinking 24 and a half heating up boys i can see it it's
integrating now you got the 24.5 24.5 i saw it 24.6
yeah i win wow
meaningless victory only if you round though i was closer
dang it now that we have our baseline
what do we need to overclock this thing as you can imagine there isn't exactly a
BIOS that you can go into and change the multiplier a wild Anthony appears in our
calculator and many older electronics the CPU speed is regulated by a resistor
capacitor or rc oscillator we'll be simplifying a bit here so if you want a
bit more of a complete explanation go ahead and watch this excellent video
from ben eater basically how an rc oscillator works is you use a transistor
or an op amp to compare the voltage between this capacitor and some voltages
we set so when the voltage of the capacitor is
below a certain threshold power is applied and then it is removed once it
hits that threshold creating an oscillating motion which gives us the
clock of our CPU to overclock in that case all we need to
do is swap this resistor out to change the
threshold
which gives us a much faster rise and fall
we're going to use that with our ti 84 to increase our clock speeds that sounds
easy enough until you see the size of the resistors that we're dealing with
we need to replace r07d
and r08d so these are the two right here
and as you can probably tell by how massive these tweezers look
they are super tiny and i am not excited
about this now this is the part that has the greatest risk of just completely
killing everything so i'm going to have to use the hot air gun while pulling on
the resistor and hope that the resistor that i want to
come off comes off and no other bits do if i slip then i might destroy
it it worked i got it off right there those
are the pads that i have to land the solder on and this is the size of the resistor in
theory we should be able to overclock it with just swapping one so what about we
only swap one see if it works
and then we can swap two and we'll have a larger range of potential overclocking
after the cameras turned off last night i kept on working on this
we had a bit of a problem you know how like you tried it as well yep nothing was
sticking to the pads turns out they were gone yeah totally gone no pads at all
ripped them right off fortunately there's another resistor right next to
it that happens to be wired up in parallel so we were able to solder onto
that one attach the potentiometer and
overclocking works now yeah it works it's not 100 stable at the moment well
that's overclocking for you yeah and i think that the reason for that is that like it needs water cooling
it needs water cooling and also like it's a resistor capacitor thing that
makes this whole clock circuit work yeah and with these long leads here we're
adding capacitance so when we shorten these to like their
final length got it it should be a lot better to make sure i understand
properly it is your intention to continue using this calculator in its
water-cooled overclocked state correct oh yeah it's like it's my calculator and
it's now going to be maybe the coolest calculator in the world and i'll be building the most ridiculous water
cooling loop you ever did see
absolutely perfect would you look at that final block assembly here we go
we're also going to have to make these leads shorter and the other thicker
leads much shorter how short do you want it uh let's not
make it much shorter so that we can shorten it later when we know how long
it needs to be exactly this is the overclocking dial you better not bump
that too far by accident a bump will be like 300 megahertz how are we going to
solder it on even what do you mean well it's going to have to be long enough that we can get at it
before we close it okay we should be able to find it
we shouldn't have cut it we should have just yeah we probably shouldn't have cut it i
knew it i had such a bad feeling about it oh that's quite a good tape job thank
you thank you Linus if anything was going to go horribly wrong it already
would have yeah you better do that better find the
hardest wood possible knock on it for days i think this RGB
reservoir sphere might be the most german thing i've ever filled with water
uh well i forgot that you had the
CPU block and these tubes were just open
on the table and i was sitting here filling the reservoir real focused on
doing a great job of pouring and the table is covered in water now the good
news is i think i've got a better idea for how to fill it now oh
just look at the block size compared to what we're actually cooling
that is about as riced out as a calculator it could be
oh there we go all right now oh there you go
is it actually circulating water in there though it doesn't look like it
well we better go fast we don't want it to overheat while there's no water flow
what is coming through oh okay good enough this thing's horrible don't
buy it she did it
yes we have a water cooled calculator
we do yeah absolutely amazing you know the funny thing is we're gonna go and
play doom again and it took so long to get this done i'm not gonna remember if
there's any difference i don't make this might actually be running faster oh
it definitely is it's actually like noticeably faster
this like dramatically exceeds my expectations
look at this like i can actually kind of move around
that's crazy because that difference is from 16 to
18.7 megahertz we can try and get just a tiny bit more
and see what it's like doing a live
speed increase is it still running yeah
okay let's just try and take in time before oh yeah it's faster it's faster
loading that map there son
look at here all right let's let's take it a tiny bit
further let's see when it becomes unstable wow look how quickly
it's loading now oh yeah that's like this is this is a big difference
it seems to be taking it let's just push it until it's you know not stable
anymore these are basically loading pretty much
instantly wow
26.8 damn
so the reason why it's getting so garbled is definitely because
it's not stable it's not stable then also it's like
the flash for some of the cycles is just not there 26 megahertz that's a whole 10
megahertz faster than before 10 million hertz if you guys enjoyed
this video you might also enjoy the series where alex and i go through the
grueling process of water cooling a red 8k camera that one was very frustrating
but as long as it's entertaining for you guys it's totally worth it right yeah
right i wasn't sure what he was going to say i'd like to thank everyone that helped
us out on this particularly the people on the chem tech forums
rs barges aka dr dinar and christopher michael aka kerm martin also virtual
flak cad for the sick ti-84 model and of course tex instruments for
the well the calculators that we didn't end up using but they still sent them it
was nice thanks to xsplit for sponsoring today's video xsplit's vcam can remove
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Linus tech tips to get 10 off at the link in the video description i'm very
happy about this it's my new favorite thing you know what you should totally do is pull a that
stupid manufacturer say water cooled RAM where
it just like has water in it and just put plugs in it and just fill the block
with water oh that was my plan oh nice i love it