'AMD vs Intel: Which CPU Cooks Better Pancakes?' - Tom's

[Fanatical Meat]

Let's clear this up as you are drowning in a glass of water and this has been dragging for too long in a thread about cooking pancakes with CPUs.


AMD couldn't get PB2 working on Zen1, so it shipped with a p-state based, rigid frequency control. This included XFR, which in the 1800X let it hit 4.1GHz on one or two cores for a short period of time.

Zen1 chips were particular in the sense that parts branded as X (1600X, 1700X, 1800X) reported TWO temperature readouts. Tdie and Tctl.

Tdie is the real measurement. This is the one that throttles the CPU if it goes too far. The 1800X's page lists max temperature as 95°C. The 1700 (non X) also lists it at 95°C. Same silicon.

Tctl is Tdie + 20°C, this is only used for fan control. Decent monitoring software like hwinfo could always see both. Some other crappy software probably reported Tctl as the real value and people with X parts were going crazy at launch time... until they noticed the exact 20°C difference with non X parts. AMD clarified it later.

This is from a friend's 1600X in hwinfo, I had to clear this up for him a little while ago

Zen1's boost was primitive and its XFR mechanism even more so, AMD thought fooling the fans to run faster to quickly get rid of the initial heat from boosting would help X parts sustain that little extra clockspeed with better cooling, which is true. This was solved with Zen+ and its Precision Boost 2 which in comparison seems alien tech. It works even better with Zen2's refined implementation.

Non X parts have Tctl = Tdie.

As a result it's just better to do an all core OC on Zen1, X or non X edition. This is not the case with Zen+ or Zen2. You can't beat the boost algorithm.


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Now, on to the pancake cooking. Intel chips can run constantly at 100°C while throttling for a while already (even running without a heatsink), whereas AMD chips tend to throttle then shut down if the situation isn't solved. der8auer's video on Zen2 without heatsink:

I think I prefer AMD's approach, better to stop the anomaly right there instead of cooking the CPU (even if it's within spec)

Well done Sir....
I like my pancakes slightly black.

Thank you for clearing this up

 

[Zucker2k]

There is no "main temp". The only temperature reported for Matisse is the hotspot temp.

What?! I actually quoted you.

That's what Matisse reports as its main temp.

Okay.

117C is entirely possible.

What? So it's possible, but not possible? See below.

It's supposed to kick in at 95C, but somehow one system managed to surge past that number. Granted he may have been throttling at that point anyway.

Okay

Let's clear this up as you are drowning in a glass of water and this has been dragging for too long in a thread about cooking pancakes with CPUs.

I got it the first time; but then we ended up with two different throttling temps, 75c and 95c and I really wanted some clarity on that because 75c just sounded ridiculous and I said as much.

AMD couldn't get PB2 working on Zen1, so it shipped with a p-state based, rigid frequency control. This included XFR, which in the 1800X let it hit 4.1GHz on one or two cores for a short period of time.

Zen1 chips were particular in the sense that parts branded as X (1600X, 1700X, 1800X) reported TWO temperature readouts. Tdie and Tctl.

Tdie is the real measurement. This is the one that throttles the CPU if it goes too far. The 1800X's page lists max temperature as 95°C. The 1700 (non X) also lists it at 95°C. Same silicon.

Tctl is Tdie + 20°C, this is only used for fan control. Decent monitoring software like hwinfo could always see both. Some other crappy software probably reported Tctl as the real value and people with X parts were going crazy at launch time... until they noticed the exact 20°C difference with non X parts. AMD clarified it later.

This is from a friend's 1600X in hwinfo, I had to clear this up for him a little while ago

Zen1's boost was primitive and its XFR mechanism even more so, AMD thought fooling the fans to run faster to quickly get rid of the initial heat from boosting would help X parts sustain that little extra clockspeed with better cooling, which is true. This was solved with Zen+ and its Precision Boost 2 which in comparison seems alien tech. It works even better with Zen2's refined implementation.

Non X parts have Tctl = Tdie.

As a result it's just better to do an all core OC on Zen1, X or non X edition. This is not the case with Zen+ or Zen2. You can't beat the boost algorithm.


-----------------------------------------------------------------------------------------------

Now, on to the pancake cooking. Intel chips can run constantly at 100°C while throttling for a while already (even running without a heatsink), whereas AMD chips tend to throttle then shut down if the situation isn't solved. der8auer's video on Zen2 without heatsink:

I think I prefer AMD's approach, better to stop the anomaly right there instead of cooking the CPU (even if it's within spec)

Thank you for the effort; and done without condescension and unwarranted accusations. Very much appreciated.

So 95c it is... @Markfw is right, and @Topweasel is misinformed.

Now, back to unpopular critic status....

Zen1's boost was primitive and its XFR mechanism even more so, AMD thought fooling the fans to run faster to quickly get rid of the initial heat from boosting would help X parts sustain that little extra clockspeed with better cooling, which is true.

So, am I far off if I say that the X parts were boosting higher not only because of superior silicon and the bigger hsf, but also because of the more aggressive fan profile (thanks to the presence of tctl), which AMD could have implemented in firmware for the benefit of non-X chips as well?

 

[.vodka]

So, am I far off if I say that the X parts were boosting higher not only because of superior silicon and the bigger hsf, but also because of the more aggressive fan profile (thanks to the presence of tctl), which AMD could have implemented in firmware for the benefit of non-X chips as well?

Non X parts already boost to their maximum factory clocks without Tctl because they're running in the comfortable range for Zen1 silicon (<3.8GHz) where the F/V curve is still manageable. XFR on non-X parts is 50MHz, XFR on X parts is 100MHz.

For example, the 1700 has a 3GHz base clock, and can boost up to 3.7GHz + 50MHz XFR = 3.75GHz if conditions allow for one or two cores. Same logic for the 1800x, but base clock 3.6GHz, boost 4GHz, XFR 4.1GHZ

It's the 1700x and the 1800x that actually push the limits because of better silicon that can do 4GHz and 4.1GHz on one or two cores for a limited amount of time, with XFR, at a sky high voltage (>1.4v) that would be dangerous for an all core OC at high currents.

The fan offset is that little extra push to get there.

Zen+ threw this all away in favor of PB2 and XFR2. Zen2 uses an even better implementation of these boost mechanisms.

 

[DrMrLordX]

What?! I actually quoted you.

You clearly didn't understand what I said. I used quotes for a reason. It reports only one temperature, NOT two. Get it right. Watch the der8auer video if you don't believe me (it has handy video of temperature reporting for an R5 3600). Matisse does not have the same behavior as Summit Ridge.

What? So it's possible, but not possible? See below.

There's no logical contradiction here. Keep fishing.

So, am I far off

Considering the context, in general, yes. For someone who wants to talk smack about a particular line of products, you have very little common knowledge about them. Everything you asked here about temp limits you could have learned with less than 30 minutes of searching in <insertsearchenginehere>. Seriously, it's all common knowledge. What was the actual purpose of this conversation? For you to learn something in the course of a few days that would take minutes of research on your own?