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90c+ CPUs

I'm pretty sure that I read somewhere a thicker base to a ln2 pot actually reduced temperatures, but I can't seem to find it. Maybe it was talking about a slow vs fast pot, which wouldn't really hold true for ambient cooling methods.
This guy gets it.

Yes some pots have a higher temp gradient than others. Temp swing on processors you're trying to heat up with LN2 can be difficult with processors or mainboards that have a cold bug. So bigger heavier pot takes longer to heat up. It also takes additional LN2 to bring the larger pots down to temp. The theory works in the opposite direction as well. However a CPU cannot heat an LN2 pot that quickly because of the surface area of the die it's self. Which is why they install a plate.

IHS = Integrated Heat Spreader. It's a must.

If they released only lidless chips, you wouldn't see processors much over 100w because a clipped on air cooler doesn't have the mass to store some BTU before dissipation. Anyone that's done extensive overclocking with socket A would understand this idea if they had tested with a plate vs naked. Almost always the plate helps. Even with an air cooler.

So plates you guys get. But don't nit pick the thickness. That was to accommodate for not having as much surface area they could have made with a different chip design, larger than 40mm.

To expand my knowledge I'd like to ask about LN2
Why do such extreme temps need to be met to get the ln2 clocks. Why can't those clocks be met at 0C or even above that. Why do they have to be brought to -90c with ln2? Why can't they achieve that on chilled water or something.
I'd love to comment at this time, but gotta blast off to work.

But in short, leakage. The cold reduces electrical leakage. @Zach_01 mentioned it earlier, but I didn't get a chance to reflect off his comments yet.

Some chips/boards will run super cold -190c. Many more do not. Those getting into Liquid Nitrogen should practice on chips capable of running a full pot like Phenom II or FX AMD processors. Then you don't have to sit there and try and maintain a -30c to keep the system from hanging up (CB CBB).

@Bones could probably fill in tons of information about LN2 as well.

Talk to you all later!
 
I'm pretty sure that I read somewhere a thicker base to a ln2 pot actually reduced temperatures, but I can't seem to find it. Maybe it was talking about a slow vs fast pot, which wouldn't really hold true for ambient cooling methods.
That's entirely possible - when you're working wiht a cooling medium that's that cold, you probably want a buffer in between it and the cores in order to have some control over thermals. Also, the boiling of the LN2 if done directly on the die would be a serious problem for cooling, as you'd have wildly fluctuating temperatures.

Of course, an LN2 pot isn't an IHS, nor is it a thermal interface as much as it is a cooler. It does the same job that your heatpipes and fins on your heatsink do - dissipate heat into another medium - just through boiling LN2 instead of heating air. And since the medium is sub-ambient and the main problem with it is too much cooling, you don't have the problem of heat soaking IHSes and coolers that you get wiht ambient coolers - turning the slow heat transfer of thicker pieces of metal into a useful buffer slowing down fluctuations rather than a hindrance for effective cooling. But this is due to the specific nature of LN2 cooling, and not anything even remotely transferable to other types of above-ambient cooling.

This guy gets it.

Yes some pots have a higher temp gradient than others. Temp swing on processors you're trying to heat up with LN2 can be difficult with processors or mainboards that have a cold bug. So bigger heavier pot takes longer to heat up. It also takes additional LN2 to bring the larger pots down to temp. The theory works in the opposite direction as well. However a CPU cannot heat an LN2 pot that quickly because of the surface area of the die it's self. Which is why they install a plate.
Yes, if we're talking LN2, which fundamentally changes how cooling operates in the first place - where the main problem is no longer dissipating heat, but rather not cooling too much. That makes it fundamentally incomparable.
IHS = Integrated Heat Spreader. It's a must.

If they released only lidless chips, you wouldn't see processors much over 100w because a clipped on air cooler doesn't have the mass to store some BTU before dissipation. Anyone that's done extensive overclocking with socket A would understand this idea if they had tested with a plate vs naked. Almost always the plate helps. Even with an air cooler.
That depends - delidded cooling can absolutely be good, but getting perfect contact with a tiny bare die is essentially impossible, especially given how fragile they are, so an IHS helps immensely with clamping a beefy cooler to the chip. Your LN2 pot, assuming it's pure copper, would still technically transfer thermal energy between the die and LN2 more efficiently without an IHS - but clamping a giant, >1kg copper pot to a 10x20mm die and expecting good contact? When good contact means microns of height difference across the die? That's not going to happen.
So plates you guys get. But don't nit pick the thickness. That was to accommodate for not having as much surface area they could have made with a different chip design, larger than 40mm.
No, the thickness is to make up for the lower Z-height of the LGA socket while maintaining AM4 cooler compatibility, as without it the vast majority of AM4 coolers would no longer have been compatible with AM5. Nor is it nit-picking - the chips would run cooler with a thinner IHS. But as I've been saying all along: as long as performance is there (which it is), then it doesn't matter. The chip doesn't care if it's 95°C or 75°C, and boosts happily until that limits. People would be more comfortable with lower temperatures, but whatever. The IHS isn't ideal, but it does what it needs to do.
 
Soo if the IHS was designed to be back compatible with AM4 coolers but if AM4 coolers can barely contain them then what's the point

Why not make it proper and shoot for a higher perf target

And about ln2 again. How exactly does being extremely cold prevent leakage? Leakage where? Are the gates being shrunk?
 
Soo if the IHS was designed to be back compatible with AM4 coolers but if AM4 coolers can barely contain them then what's the point

Why not make it proper and shoot for a higher perf target
Because they're already hitting what is essentially the ambient cooling performance ceiling for these chips with this cooling. You need to go sub-ambient for meaningful differences over what this delivers with a decent AIO even if that is hitting 95°C. So the only things they would gain from ditching AM4 cooler support would be lower temperatures at the same performance and thousands of annoyed customers. And that's a pretty easy choice, IMO.
 
That's entirely possible - when you're working wiht a cooling medium that's that cold, you probably want a buffer in between it and the cores in order to have some control over thermals. Also, the boiling of the LN2 if done directly on the die would be a serious problem for cooling, as you'd have wildly fluctuating temperatures.

Of course, an LN2 pot isn't an IHS, nor is it a thermal interface as much as it is a cooler. It does the same job that your heatpipes and fins on your heatsink do - dissipate heat into another medium - just through boiling LN2 instead of heating air. And since the medium is sub-ambient and the main problem with it is too much cooling, you don't have the problem of heat soaking IHSes and coolers that you get wiht ambient coolers - turning the slow heat transfer of thicker pieces of metal into a useful buffer slowing down fluctuations rather than a hindrance for effective cooling. But this is due to the specific nature of LN2 cooling, and not anything even remotely transferable to other types of above-ambient cooling.


Yes, if we're talking LN2, which fundamentally changes how cooling operates in the first place - where the main problem is no longer dissipating heat, but rather not cooling too much. That makes it fundamentally incomparable.

That depends - delidded cooling can absolutely be good, but getting perfect contact with a tiny bare die is essentially impossible, especially given how fragile they are, so an IHS helps immensely with clamping a beefy cooler to the chip. Your LN2 pot, assuming it's pure copper, would still technically transfer thermal energy between the die and LN2 more efficiently without an IHS - but clamping a giant, >1kg copper pot to a 10x20mm die and expecting good contact? When good contact means microns of height difference across the die? That's not going to happen.

No, the thickness is to make up for the lower Z-height of the LGA socket while maintaining AM4 cooler compatibility, as without it the vast majority of AM4 coolers would no longer have been compatible with AM5. Nor is it nit-picking - the chips would run cooler with a thinner IHS. But as I've been saying all along: as long as performance is there (which it is), then it doesn't matter. The chip doesn't care if it's 95°C or 75°C, and boosts happily until that limits. People would be more comfortable with lower temperatures, but whatever. The IHS isn't ideal, but it does what it needs to do.
I think you're basing your comment on the assumption that the IHS is an insulating layer between the CPU and the cooler when it isn't. You need material in your heat spreader, otherwise the tiny CPU cores only come in contact with a small fraction of the cooler coldplate - which I guess, can work when the cooler coldplate spreads the heat itself, but would be a terrible idea with a cooler with direct contact heatpipes (one or two pipes would touch the cores, the others would stay cold). If more material was a bad thing, then smaller coolers and radiators would be more effective than big ones.

I've got a 35 W Core i7 4th gen cooled by a passive block of aluminium which essentially works as a gigantic heat spreader. And indeed it works as the CPU warms up very slowly and never exceeds 60-62 °C.
 
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Because they're already hitting what is essentially the ambient cooling performance ceiling for these chips with this cooling. You need to go sub-ambient for meaningful differences over what this delivers with a decent AIO even if that is hitting 95°C. So the only things they would gain from ditching AM4 cooler support would be lower temperatures at the same performance and thousands of annoyed customers. And that's a pretty easy choice, IMO.
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
 
Soo if the IHS was designed to be back compatible with AM4 coolers but if AM4 coolers can barely contain them then what's the point

Why not make it proper and shoot for a higher perf target

And about ln2 again. How exactly does being extremely cold prevent leakage? Leakage where? Are the gates being shrunk?
Most AM4 coolers can handle the increased power draw of an AM5 processor. (excluding the cheapest ones ofc.)

Mostly the thick IHS is capable of transferring the heat, but due to its high thermal capacity, it requires a higher delta to move the heat across at the same speed.

At lower boost clocks (AKA not benchmarking) it should show improvement on smaller coolers, as the IHS will absorb the sudden boost of heat.


The incredibly low temperatures reduce the leakage due to weird physics stuff. Quantum tunneling becomes a thing when transistors go that small. The simple explanation is that the less spare thermal energy there is, the less the electrons tend to drift around. This increases stability by not corrupting differential charges across transistors, reduces the voltage required as less is wandering off, and reduces power draw.

I think you're basing your comment on the assumption that the IHS is an insulating layer between the CPU and the cooler when it isn't. You need material in your heat spreader, otherwise the tiny CPU cores would only come in contact with a small fraction of the cooler coldplate. If more material was a bad thing, then smaller coolers and radiators would be more effective than big ones.

I've got a 35 W Core i7 4th gen cooled by a passive block of aluminium which essentially works as a gigantic heat spreader. And indeed it works as the CPU warms up very slowly and never exceeds 60-62 °C.
Heat spreaders are very necessary for air coolers, as heatpipes do not share the heat with each other very well. Only the pipes directly contacting the CPU will remove heat. However, every material has a thermal conductivity, so every material insulates. A thicker IHS will tend to reduce the speed of heat removal once you get thick enough to spread it across the full surface relatively evenly. Your Aluminum block is capable of dissipating the 35W across its entire surface area sufficiently and has enough surface area to dissipate 35W into the air, therefore your temperatures are stable. If this is not under sustained load, then what is happening is the block is absorbing heat spikes and is capable of dissipating your average power draw with the ~30-40 degree delta between CPU and ambient.
 
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
It simply auto-oc once thermals are lower than the limits. That happened during all Zen arch cpus.
 
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
I'll give you that, yes they did.

But that same CPU release like the one before had circuits to make it auto overclock, to it's reasonable max, that anyone could get with reasonable hardware, FOR EVERYONE.

Automatically.

Anyone who has tried to Oc the earlier Ryzen found out the gains were small without THE same exotic cooling, AMd had pretty much maxed them.

So some of us already have 2X 360 rads, that were not bought years ago for nothing.
 
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
The unlocked CPU concept is fading more and more like the static OC with every new generation.

For the avg user that is...
 
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
Locked or unlocked only matters of you're hitting max boost limits. If your limit is power or heat, you can't OC anyway.

You can consider it as being limited way under max boost clocks. Or you can consider it as being auto OCd up until the CPU runs into any limit. I prefer the latter. :)
 
I think you're basing your comment on the assumption that the IHS is an insulating layer between the CPU and the cooler when it isn't. You need material in your heat spreader, otherwise the tiny CPU cores only come in contact with a small fraction of the cooler coldplate - which I guess, can work when the cooler coldplate spreads the heat itself, but would be a terrible idea with a cooler with direct contact heatpipes (one or two pipes would touch the cores, the others would stay cold). If more material was a bad thing, then smaller coolers and radiators would be more effective than big ones.
Lol, I said pretty much exactly the same thing a few pages back - that direct touch heatpipes is the one case where you absolutely need an IHS (though I guess we can add LN2 to that list as well). Non-direct touch coolers have that spreading layer built in. But it is an insulating layer - everything that isn't a heatpipe or water is. It slows thermal dissipation - but it also spreads heat out. The question is whether it does too much of the former vs. too little of the latter. Which is the case if the IHS is too thick, and thus why a thicker IHS leads to higher core temperatures, as the thermal equilibrium of the setup rises in tune to the higher thermal resistance of the IHS.
I've got a 35 W Core i7 4th gen cooled by a passive block of aluminium which essentially works as a gigantic heat spreader. And indeed it works as the CPU warms up very slowly and never exceeds 60-62 °C.
That's quite impressive, but you're just demonstrating that you can hit thermal equilibrium with all kinds of setups, and that this one has such a low heat load that even a large thermal mass with very little surface area relative to its mass can still do the job in this case. That doesn't mean it's any more efficient than if that same mass consisted of heatpipes and fins, after all, nor that it wouldn't likely work the better without an IHS (given good flatness and contact). And, of course, the discussion is considering the effect of IHS thickness assuming all else is equal (otherwise it's literally impossible to discuss).
So they've released an unlocked cpu than pretty much can't be OCd unless you're on ln2?
Yes, as has been the case for pretty much every generation of Ryzen. You can achieve minor OCs (especially in multicore, but also some boost clock) with PBO offsets and CO tuning, but you're not getting a stable static OC above boost clock without exotic cooling.
 
What about my Ryzen chips? I have been suspecting that they possibly can't handle 90C (Windows suddenly rebooting during the same tasks, where it's known to be stable, with "WHEA_UNCORRECTABLE_ERROR" reported in the event log, with the reason being "Cache Hierarchy Error" every time with my Ryzens, both the Ryzen 7 3700X and Ryzen 5 5600X)

I only saw this happening with a warm room, 95 percent or roughly 95 percent of the time!
 
What about my Ryzen chips? I have been suspecting that they possibly can't handle 90C (Windows suddenly rebooting during the same tasks, where it's known to be stable, with "WHEA_UNCORRECTABLE_ERROR" reported in the event log, with the reason being "Cache Hierarchy Error" every time with my Ryzens, both the Ryzen 7 3700X and Ryzen 5 5600X)

I only saw this happening with a warm room, 95 percent or roughly 95 percent of the time!
Sounds like the Vcore is a little low at stock and the increased leakage at 90C is causing low voltage instability. The 7K series apparently has an aggressive Vcore at stock, which is one of the reasons for the high temps and power draw.
 
My reboots usually come after 100c sometime :D
 
I don't get it.

Running a CPU pegged at its max boost clock is fine. Running a CPU pegged at its max power limit is also fine. But running one pegged at its temperature limit while still maintaining boost is suddenly not fine?

Or did you want AMD to release Zen 4 with base clocks of 3.5-4 GHz and max boost clocks of 4.5 GHz at 75-80 °C? What difference would it have made?

The only thing AMD did with Zen 4 is they've set it to auto overclock up to whatever your cooling can handle so you won't have to do it yourself.
 
Lol, I said pretty much exactly the same thing a few pages back - that direct touch heatpipes is the one case where you absolutely need an IHS (though I guess we can add LN2 to that list as well). Non-direct touch coolers have that spreading layer built in. But it is an insulating layer - everything that isn't a heatpipe or water is. It slows thermal dissipation - but it also spreads heat out. The question is whether it does too much of the former vs. too little of the latter. Which is the case if the IHS is too thick, and thus why a thicker IHS leads to higher core temperatures, as the thermal equilibrium of the setup rises in tune to the higher thermal resistance of the IHS.

That's quite impressive, but you're just demonstrating that you can hit thermal equilibrium with all kinds of setups, and that this one has such a low heat load that even a large thermal mass with very little surface area relative to its mass can still do the job in this case. That doesn't mean it's any more efficient than if that same mass consisted of heatpipes and fins, after all, nor that it wouldn't likely work the better without an IHS (given good flatness and contact). And, of course, the discussion is considering the effect of IHS thickness assuming all else is equal (otherwise it's literally impossible to discuss).

Yes, as has been the case for pretty much every generation of Ryzen. You can achieve minor OCs (especially in multicore, but also some boost clock) with PBO offsets and CO tuning, but you're not getting a stable static OC above boost clock without exotic cooling.
Exactly. You need the heat spreader to spread the heat to larger surface, but not too thick to act as a storage. You need only a passthough to wider area.
I don't think you're right about this though. I'm quite convinced that the only reason for the Ryzen 7000 IHS is maintaining cooler compatibility with AM4 coolers. There's nothing else they could have made thicker - making the socket taller would have been hell with all those pins and their spring force; making the substrate thicker would be expensive and wasteful. There isn't anything else to change to make up the height difference between AM5 with a thinner IHS and the bottom of an in-spec AM4 cooler - so they thickened the IHS to fill the gap, to maintain the same Z-height between the two.
Could be this too yes, or just this...
 
I don't get it.

Running a CPU pegged at its max boost clock is fine. Running a CPU pegged at its max power limit is also fine. But running one pegged at its temperature limit while still maintaining boost is suddenly not fine?

Or did you want AMD to release Zen 4 with base clocks of 3.5-4 GHz and max boost clocks of 4.5 GHz at 75-80 °C? What difference would it have made?

The only thing AMD did with Zen 4 is they've set it to auto overclock up to whatever your cooling can handle so you won't have to do it yourself.

Neither of the things that you've just mentioned is fine. If someone wants you to believe it, then they simply want to sell you something bad.

Hot air is not fine - keep it mind that your case exhaust will put that air in your room.

It's an engineering fail:

Igor's cooler testing shows that none of the air coolers can maintain CPU temperatures below 90C under load with the AMD Ryzen 7000 CPUs while liquid coolers can allow around 75-80C temps if you are running a really good setup with lots of airflows.
 
Neither of the things that you've just mentioned is fine. If someone wants you to believe it, then they simply want to sell you something bad.

Hot air is not fine - keep it mind that your case exhaust will put that air in your room.
CPU temperature and case temperature are not the same thing. I learned this with my R5 3600 experience. The CPU was running hot, but the be quiet! Shadow Rock LP sitting on it was cold to the touch no matter what PPT setting I used. The CPU just wasn't transferring its heat to the cooler efficiently enough. I had to decrease PPT all the way to 65 W for CPU temps to be tolerable in an airflow-restricted Aerocool CS-101 case. I didn't have this problem with the i7 11700 that I could crank up to 125-130 W before I got bad temperatures. The cooler got warm together with the CPU, unlike with the 3600.

Link is in my signature, if you want to read about it in detail.

Edit: If I knew what I know now about temperature limits back then, I probably would have kept the 3600. Oh well. :rolleyes:
 
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Neither of the things that you've just mentioned is fine. If someone wants you to believe it, then they simply want to sell you something bad.

Hot air is not fine - keep it mind that your case exhaust will put that air in your room.

It's an engineering fail:
I think you've missed about 5~6 pages of analyzing this

You're not supposed to cool this CPU under 95C only to dissipate more heat and let it boost high, if max performance is the goal. Der8aur likes tool/LM sales...
Nothing has failed except from some old (in thought)people that cant wrap their brains around it.

Let me ask you this:

Which CPU from those 2 below will heat up the room faster?

Constant long term values:
1. 220W at 95C
2. 220W at 80C

How about these 2?

Constant long term values:
1. 215W at 95C
2. 220W at 80C
 
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Neither of the things that you've just mentioned is fine. If someone wants you to believe it, then they simply want to sell you something bad.

Hot air is not fine - keep it mind that your case exhaust will put that air in your room.

It's an engineering fail:
Have you missed Intel's last few releases, not many of those top end chips were known for they're low testosterone(mwahhhhaha I meant temperature, dick of a phone)

Funny you better slate Intel's new KS when it's arse by your ideology.
 
Have you missed Intel's last few releases, not many of those top end chips were known for they're low testosterone(mwahhhhaha I meant temperature, dick of a phone)

Funny you better slate Intel's new KS when it's arse by your ideology.
If that was unintentional, you have entered the DYAC hall of fame.

If you have hot air pouring into your room from this CPU, I would encourage you to observe the TBP of recent generation GPU's, and the TDP and whatever they call PTT of Intel CPU's.

Also, you need to boost your case fans because the delta T of air through your computer case should not be high, or you are starving your components of air.

Ryzen is now doing the same thing as Radeon, Core, and GeForce to remain competitive.

If we don't like it, maybe we shouldn't have bought the products that did it.
 
My only though to this is do you think case design will change again for CPU's like it did with larger GPU's & the removal of the disc drives for better airflow?

What's next for case desgin? Baffles to keep hot GPU air from Flowing up the CPU's because the increase in wattage?
Or do w need to go back to Blower Cards?

I'm not a fan of these new heatsinks on cards that blow hot air all around the case. I prefer when the air flows out the back of the case.
I was recently looking at two AMD graphics cards from the same board partner that were only 20 watts away from each other. I noticed the main difference wasn't size of the heat sink it was weight the higher wattage one weighed more by 1/4 of the less wattage. The fin orinitation was different too one Horizonital the other veritcal, but they both had the same fans.
 
I mean, it's a 3 year warranty.......they're not promising 10 years. For all the bitching about Intel 4C/8T, we got generations of hella long-lasting CPUs......but none of that was promised.
But isn't that exactly why we should distrust AMD's and Intel's statements that "its' fine" to run at these high temps? After all, they would rather just sell you a new CPU after 3 or whatever years... Personally, I have no interest in squeezing out the last drop of performance out of my hardware (at least through hardware measures) and so I have a very conservative setup that I hope can last 10 years or more if necessary.
 
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