Who REALLY Runs Hotter? AMD vs Intel

i'm really excited about this video guys if you believe what intel tells you you'd think that this core i9 9900k 8-core processor is a 95-watt cpu while if you believe what amd tells you you'd believe that this ryzen 7 3800x also eight core processor is a 105 watt cpu so then clearly if amd's number is higher and intel's number is lower that rise in cpu it's gonna run hotter and kick more heat out into your room right actually not necessarily so as it turns out there is no industry standard way that we can all agree on of reporting the power consumption or the tdp of a computer processor so those numbers that i was talking about before well it turns out it's up to third parties in the media to investigate who is representing their product realistically and who is painting a rosier picture than reality well get on with it then so on our table here we've got two benches one for team blue one for team red with our eight core cpus installed to keep everything equal we're running our memory at the same speed between them and they're each running a fresh install right yes fresh os install on a pci express gen 3 drive remember guys intel doesn't have a consumer pcie gen 4 chipset yet now here's the tricky part measuring the total thermal energy output of a cpu is not as simple as just strapping the same cooler onto them running prime 95 and then recording the temperature because of differences in die size ihs solder quality software reporting accuracy etc it's actually possible for a processor to be outputting more heat while registering a lower temperature or vice versa so what anthony's been working on is a way to instead capture as much of the heat from our processors as possible into a known thermal mass then measure the rise in temperature of our thermal mass rather than the reported temperature of our cpu now before we can do this we have to prepare a couple of things normally you'd never insulate the back of your motherboard and it's power delivery components that's a great recipe for premature failure but we want as much of the heat going into our thermal mass to be from the cpu as possible so sorry motherboard times two we also need to insulate our mint julep cup here that way we can plot the change in the water's temperature over time without worrying so much about the heat that we are losing to the surrounding environment through the metal walls of our cup not all containers have insulated walls like the ltt water bottle which keeps your drink cold on a hot day lttstore.com now let's take a look at how we're mounting our thermal capture device to the cpu honestly even compared to zip ties this is going to be pretty sketchy but we need to make sure that we could see the coolant inside while maintaining the same mounting pressure on both systems and a weighted piece of glass ticked both of those boxes now you guys might be wondering if all we need is a thermal mass why use water why not just put a big hunk of metal with an embedded thermal probe on top of the cpu and the answer of course is that that's not nearly as much fun to look at enter thermochromic ink this stuff comes from lcr hall crest and it's called chromogen and what it does is once the water reaches 80 degrees celsius the ink will begin to change color from white to black basically whoever hits that point first is outputting the most heat since this is permanent we'll have to be sure to add the same amount for each run uh we didn't bring a syringe so do you want to just pour a cap full uh yeah sure i can try okay sure and it goes whoa give a little mix with our k-type probe that's what those are for right yeah and we'll go ahead and don't get cut by the edges of this glass please so we've got just about 300 milliliters of water in there and then our ink probably puts us somewhere in the neighborhood of about 325s about a tablespoon of ink so ah let's go ahead and turn on the machine that sounds like an idea not sure if it's a good idea all right let's fire up our thermal probe here 10 degrees so you guys might have noticed that our coolant is pretty chilly that's because we put it in the fridge before we started to make sure we had a little bit of time to boot up the system before we needed to start the test so the plan is to hit go on blender here at exactly 22 degrees celsius so i'm gonna go ahead and hit it with uh with a load here to try and heat up our water a bit okay so we ran into a slight problem the instant we fire up any kind of cpu intensive load our processor temperatures go to thermal throttling territory boom which means that we are not getting the full power out of the chip because it's holding itself back we unfortunately selected a stainless steel vessel for our water and dye solution but no worries the good folks at madrina's have us covered they shipped us these weird camping cups and alex found one so we are going to uh convert this to be our cooler now do you think it's steel do we have a magnet that won't tell us if it's stainless steel wish us luck so good news and bad news alex good news is i removed the bottom of the cup the bad news is there is a whole lot of space in between the one bottom and the other more different bottom cup number two there we go okay so after a bit of milling alex has gotten us this little disc here and as you can see it's got a little bit of a cut out here on the inside and what we can do is just slot our cup right into that mix this up put it around the edge and it should be watertight within about 20 minutes i never said i was good at arts and crafts i am measuring out wait why is this milky oh wait what it was in the cap so we're back 300 mils of water oh wow we kind of need more now so we're back 400 milliliters of water later we have a slightly larger vessel this time let's use this cap this time let's put on some fresh thermal compound i see you just cleaned it off okay it's a little on the heavy side but should be okay and schwippity schwampty does it fit please tell me it doesn't interfere with anything well there's only one way to find out let's fire this mess up are we missing anything um aside from like the probe the glass yeah aside from that no i just want to know if it thermal throttles well we're not going to have the mounting pressure ah that's fine i can just push on it show me the blender that looks like good news cpu temperature is actually reasonable 35 is way too high yep thermal throttling i don't think it's making proper contact uh that's fine i can just push on it all right i sanded off the side let's see if it's a contact error or if we just have a different problem so it looks like it actually is working but we just need a little bit of coolant flow within the container and that dramatically affects our cpu temps and then once it's moving the heat from the cpu causes more convection yeah we are turboing to 4.0 4.1 gigahertz across all cores right now so we may be in business although i have a new problem um that i identified if we actually wait until the coolant reaches 80 degrees no matter which cpu it is it will have long thermal throttle before then right right so i was trying to avoid this but we are just going to do this the simple way with a very short loop we've got a reservoir a pump and a cpu block no radiator no fans because remember we want our water to absorb the heat and we want to track the changes in temperature over time now we do introduce the variable of our pump actually giving off some heat into the loop but given how significant our cpu is as a heat source i don't expect it to cause too many problems with that said i predicted lots of things today that weren't going to cause too many problems and yet here we are so are we going to run the reservoir without the cap on yes why don't we start with 500 mils that should be a pretty good amount for this loop actually that might be too much 400 mils here we go ah crap is it leaking no it's just not a lot of water so that was what 250 mils it's a cup yes something went right so let's do a quick cinebench r20 run our coolant temperature is 16.5 degrees which means we've still got time we are turboing over 4 gigahertz we're at about 4.2 and our hottest core is about 51 degrees right now so this is exactly the behavior that we are looking for so we've decided we're gonna formally start our graphs once the cpu hits 100 load and it begins actually completing the render so that put us at it somewhere in the neighborhood of around 28 degrees so now all we got to do is strap in and see how long this takes before it gets hot so it's been about uh five minutes of actual render now and we're up to about 43 degrees we need uh we need another 35 degrees and then theoretically this will turn black it'll be pretty sick unfortunately we only have about another 25 degrees to go before we thermal throttle so it might go a little slower for that last 10 degrees yeah what's it currently sitting at 75-ish what's the clock 4.2 4.1 4.2 that's a little high i think it's multi-core enhancement enabled oh well we were planning to run it twice anyway weren't we yeah oh wait well hold on a second we were chit-chatting there and well this color change die sucks because it starts changing colors at like 60 degrees well unless it got hotter in the blog so why don't we just ride this out to 100 degrees when the cpu starts really thermal throttling and then we'll just plot it yeah so we are on the brink of thermal throttling now our coolant is at 68 degrees uh core number two is at 99 degrees we're actually still running at 3.8 to 3.9 gigahertz so uh pad respect for that i guess but we're gonna have to shut this experiment down pretty quickly of course though we would be remiss if we didn't wait until uh we got another 0.3 degrees on here and then we can let it end so we made yet another observation this time it was that the settings that our cpu was running at weren't really stock and they weren't really multi-core enhancement either what the why is this a greater volume of water this time i could have sworn it was oh wait did i say 350 mils last time i might have missed a hundred mils there let me put in exactly 100 mils and see if that makes up the difference nope that weren't it absorb absorb my pretty this is not going to be in the video okay so a couple rough things happened yesterday did this system just hard reset what all right so we learned a lot yesterday we got this cool graph of our water temperature over time and all that good stuff but even just on intel alone that's not the complete story because yesterday we were running the default behavior so intel's stock with multi-core enhancement disabled but a multi-core enhancement allows your cpu to boost for a longer period of time so for this run here we have enabled multi-core enhancement and we're going to go ahead and hit it again once we hit 22 degrees round number two here we go we're turboing to 4.7 4.8 ish seems good we're not expecting a difference here though we're just expecting it to stay at its maximum turbo frequencies for longer come on baby five start blending me six seven eight nine there it goes 27.5 okay good enough all right let's see how she heats up now this is weird we're only about a minute into our render and our slowest cores are already sitting at 4.1 gigahertz that's not very enhancing is it no that's like slightly behanced still i don't remember seeing 4.1 at this stage of the game last time around no 4.1 didn't happen until like i want to say 10 minutes in okay so as you can see our liquid turned dark and that means that this test is done uh it hit 69 degrees like our last one at about 16 16 and a half minutes for now it looks like multi-core enhancement did nothing more than increase the thermals [Music] weird now i just need to take my ice water fill it up and fire it up we are using xmp i figure that with amd cpus anyway the performance of the cpu and therefore how hot it gets it's going to be broadly determined by the speed of the ram so if we use 2133 memory or something like that it might not be a fair test it's actually a little funny it's not warming up as fast as the intel cpu did so 21.5 i'm going to stop prime95 switch back over to blender and then when it hits 22 i'm gonna start it off 4.1 gigahertz and only 42 degrees on our coolant that seems pretty similar actually similar now that i look at it yeah but it seems to be tracking a little bit lower a little lower so we're going to need the full length of our run in order to find out whether or not amd is actually outputting less heat here okay so we're almost 11 minutes into our test at this point our water is currently at about 56 degrees celsius now if we check and see where we were at 11 minutes on our 9700k it was actually 58 so we're still a couple degrees colder it's starting to look like the uh the processors are are separating we're at 63.5 degrees and 15 minutes in intel was at 66 degrees so it looks like even given amd's higher rated tdp their cpu is actually outputting less heat one thing that we probably won't graph just because that wasn't really the point of the video but that we thought was interesting at the end of the test intel had rendered around 300 tiles and change whereas even now almost complete on the amd side of things we've done nearly 1900 so that's uh well that's that's rough that's rough what's our current time at our current time is at 20 minutes and 23 seconds okay we're at 67.2 degrees so yes our amd processor did output less heat so then why is it that our results seem to differ from what both amd and intel state on the packaging the answer is that it comes down to how the two companies measure tdp intel measures tdp based on recommendations for cooling solutions assuming the processor will run at its base frequency in other words their number is intended as a guideline that system integrators can use to avoid thermal throttling not necessarily to allow the cpu to turbo up to its maximum all the time by contrast amd measures their tdp as the maximum power a processor can draw for a thermally significant period while running a typical load and that might seem like the same thing but thanks to precision boost it's not amd's ryzen cpus will attempt to run at the fastest possible speed at all times similar to a modern gpu and this is where amd measures their tdp so if intel were to measure their tdp this way they would actually have to measure it with their turbo boost limiters disabled which would make it measurably higher now the thing is i don't think either of us is in a position to propose like an industry-wide uh way of standardly measuring tdp clearly we're not in that position it'd be nice though what we do know is that having everyone go their own way on this is harmful to consumers who use this spec as a way to choose between one product and another so in the long term hopefully the major players in the industry can come together and standardize on a way of measuring but in the meantime the best advice we can give you is to just ignore it unless you're comparing apples to apples so like within intel's own product lines and even hopefully the same product families and rely on independent reviews like our recent video card buyer's guide which actually anthony hosted they should go check that out right yeah sure heck yeah so thanks for watching guys hope you enjoyed it see ya

Channel: Linus Tech Tips

Views: 2,156,167

Keywords: amd, intel, core i9, ryzen 7, 9900K, 3800X, heat, output, watts, tdp, investigation, experiment, cooling, jank, science, workshop, Blender, thermochromic, ink, cpu, processor

Id: 6u4ew6IT4Vo

Length: 19min 15sec (1155 seconds)

Published: Mon Sep 16 2019

Reddit Comments

[u/Lord_Trollingham]

I unusually really like videos with Anthony but this one is flawed on practically every level. Why not simply measure the change in collant temperature on a heavily insulated loop and then calculate how many joules it took? Or submerge the radiator of an AiO in a known quantity of water and measure the increase in water temperature?

[u/redsunstar]

Or they could have integrated the measured power consumption over time, and they'd have an energy figure. Either with the onboard sensors, or with an oscilloscope on the relevant rails.

I don't believe for a single second that this didn't occur to them, or that doing it as a sanity check would have been over their abilities.

But LTT doesn't think it would have given them the same amount of views. Apparently, they decided that bumbling around was endearing. TBH, that's really disappointing when they know they can have a more sensible and rigorous approach but they keep away for it because they think it's fewer views.

[u/T1beriu]

Anthony, I was expecting such an unscientific methodology coming from Linus, not from you.

[u/[deleted]]

Oh god.. LTT and ‘science’...

This gon be ‘good’.

[u/mynumberistwentynine]

I watch LTT mainly for entertainment and really enjoy most of the stuff they do, but every so often they'll have a cool idea I'd like to see explored and sadly it usually ends up with half-baked and rushed execution. Just like this video did. It's a bummer.

[u/davidverner]

They didn't drop anything.

[u/Meomeo888]

This is good idea, but fail in work. We need test to compare 2 systems with the same CPU Cooler, Sensor at IHS, the same stress test.

[u/xRadec]

So much unnecessary work done on this video. Jesus..

[u/n2k12]

intel runs hotter.