 Yeah, great search where to buy did you key and ate a fruit? Thank you. Did you key every single week later user power of engineering? Oh, yes, you find the things that you need on digikey.com. What is a great search? Week, okay, so this week, um, you know one thing I look I do before we you know do the show is I always look like oh what you know I Search social media for like find or search and the word digikey and just be okay. Somebody who's like I can't find I'm looking for something on digikey and You know some of them actually already covered like somebody was like oh I need machined pens and I was like I already covered that I was gonna do that as the great search, but we already did that before But this one is was kind of interesting So I've never I've never heard of this material before so people who are doing like overclocking of CPUs and GPUs, you know you need to Water cool or like air cool the CPU like, you know this the pi 5 now has an air cooling add-on and You know, you have this cooling fan or this heat sink whether this water cooler and then you have the CPU itself and you have to attach the CPU to the thing that's cooling it and You want the thermal transmission to be as good as possible between the two and traditionally people use thermal paste and You know thermal paste I don't know if anyone like if you've ever put together a computer comes in like, you know You'd get your CPU kit you put the CPU down and then you squeeze this stuff and you kind of like, you know Slurp it around and then you clamp the heat sink on and like there's these little clamping bits and the paste fills in the gaps and makes like a near perfect Thermal connection between the heat sink and the CPU and so apparently there's this other kind of material called Thermal pads, so I've always used paste but I have seen thermal pads once in a while and thermal pads are as you can imagine very thin Pieces of material and they're less messy than paste and you never have to clean it off You just you stick it on remove it and they have a benefit of they can also be a gap filler like if you don't you know one of the risks of Clamping the heat sink on the CPU is like you clamp a little bit too hard You could crack the CPU you want it to be like exact but like exact no no more and no less too big Not enough thermal transfer too little. You just like to storage your CPU and that's really tragic So thermal pads, you know, they have a little bit of give and the one that they're talking about in particular is called cryo sheet and like I Have no skin in this game I don't know anything about this product or what this is used for so you know NB notabain I did not an expert at this but You know, this is you know 15 bucks for a one inch by one inch sheet And I was like oh well I'm gonna look up and try to find the specifications for this You know like what is the thermal resistivity of it and there is no published them or resistivity? And so again, I know nothing about this market But let me tell you as an engineer if you're buying a product like this that's meant for thermal heat sinking or like Thermal transfer and there's no specification. They're like you can't know if it's any good or not because it isn't like Thermal resistivity isn't a feeling. It's a number and so if the number isn't there There's no way for you to compare it and I think that's part of their thing It's like, you know, they don't publish the number They just say it's the best and you just sort of have to trust it. So let's show how you can find on digikey Graphite thermal pads that do have numbers published with them and so you can actually compare them one to the other Okay, so go to digikey and you know, is it better than this other? Cryo thing. I don't know but I want to show you how to find the real deal and then you know You can compare and contrast and do testing with it Okay, so let's look for thermal pads So they've got it Pads and sheets 8,000 items and I'll say you know, they have like of course Heat sinks and peltiers, you know active coolers Water cooling thermal paste but pads and sheets again, they're easy to apply like, you know If you're doing if you want to remove them adjust them You know paste is gonna probably be a better because it's thinner but for just for the raw thermal transfer numbers But there might be times you want pads and sheets. Okay, so as usual we go to stacked and we're gonna only look for active Items and then in stock Just not that there there might be stuff, you know, that is better that's not in stock But we only want to see what's available Next up, you know, I don't think we care too much about the acrylic adhesive, you know You know, maybe you want adhesive. Maybe you don't maybe that's not as important But we do want is the thermal resistivity and we want to have like the lowest thermal resist Well, sorry, let's look for the thickness first because the thickness was kind of you know important things so Sheets eyes So These are Point two millimeters thick, so let's look for about point two millimeters So if you go here, you can see This is exactly point two. Well, let's be a little bit flexible, you know, maybe up to Point two five maybe as a list point one five So we have like, you know a range where we want thinner sheets in general Okay, you'll notice for If I select graphite the thermal resistivity for you know graphite is it's going to be the lowest ones But let's instead of just you know specifying graphite just in case there's like other materials We're going to just go with, you know, the lower Maybe the, you know, look, you know point five degrees See per watt or lower That gets us down to 42 options And so you'll see like there is some very low-cost ones that are, you know, 70 cents But these are small. They're designed for to 220. So there's when you have like a specifically a to 220 LDO or transistor or IGBT or whatever and you know, you don't want to like cut and drill a little hole for that You're the back part of a to 220 is like that nice flat metal heat sinking part And you put that between that in the heat sink and then use a screw to connect it And that's what that hole is for is that's where the hole goes through the screw goes through to clamp that transistor or LDO to your Heat sink with the little pad in between But we don't want that we actually want like something like this because we want To be able to cut our own pieces out Although I'll be honest like, you know, if this is the right, you know If the to 220 pad happens to be the right shape and you don't mind the hole or we get a version without a hole That's fine. But let's let's look at Larger pieces of the cryo sheets. Yeah, they do have a small 24 by 12 millimeter, but I actually think like most chips are you're gonna like a GPU or CPU You're gonna want to have at least one inch by one inch. It's not more. So let's in outline Let's just only pick At least, you know one inch on one direction, but you'll you'll notice that there's there's gonna be a lot bigger ones and then Finally, there's a lot of Marketplace options as you know pieces as well So maybe we'll get rid of the marketplace. Although these are, you know, you can always get these pieces if you want those You can take a little longer to ship. So let's just look at what's available in stock and Looks like there's a couple options For, you know, thickness and the thermal resistivity, you know, I think we can Look for the the lowest resistivity. So We'll start from the bottom up. So this is the most These are the best pads for this this is kind of a vague one, but it looks like it's just like a gray pad This one is pretty it exists. These are rather large. It's a 600 by 450 millimeters But this one is fine, you know, this one even has adhesive on it and 450 by 300 milliliters millimeters You compare that against, you know These sheets that are like, you know, 20 bucks one inch by one inch or something this piece is You know, $20 or, you know Or less you get a smaller piece and you get something that's literally 100 times as large so you can cut any size you want as many GPs or CPS as you desire, you know, you keep this around And just cut out of it as as needed any shape you want and so this this one I think is my gonna be my bet So it's a tiny bit thicker than 0.2 millimeters. It's 0.254. So it's like, you know 0.1 0.01 inch So as long as it's, you know, not too thick but again, you want it to be a tiny bit thick so it adds a little bit of The cushioning fills in the gaps and if it's if the clamping isn't perfectly even it will still make good contact And it has adhesive as well, which is great and Yeah, and then there's also a data sheet if you need it. So, you know, what I like is that there's specifications for everything They do come in different sizes and looks like all these are graphite Oh, one thing to watch out for graphite is it's electrically conductive. It's not isolating. So some Materials that you use for heat sinking or are thermally conductive but electrically isolating graphite is both electrical and Thermally conductive. So if you look down here at the ohms, it's basically Zero ohms. It's basically like perfectly conductive. So make sure that, you know, it's okay if you know if that's grounded It's earth grounded Make sure that it's okay for that to be touching your CPU Some Some past transistors or LDOs of knows that the heat sink is electrically connected to like the V in or the V out line. It's not ground You really don't want to accidentally ground it to the case or something through this material So something to watch out for so This sheet there's also a sheet. That's much thinner if you you know want point one two seven millimeters. This is the 462 series 463 both are in stock Get a gigantic sheet and you can just cut off pieces as needed and that's my great search That's great search