<story><title>Beating Jeff&apos;s 3.14 Ghz Raspberry Pi 5</title><url>https://jonatron.github.io/randomstuff/pivolt/</url></story><parent_chain><item><author>K0balt</author><text>I still remember my dual celeron 450 clocked to 900 mhz.  Those chips ran rock solid at double their rated clock, no didling the voltage or anything.  Just needed decent cooling.  Never mind that at the time having 2 processors was nearly useless.</text></item><item><author>metadat</author><text>That&amp;#x27;s pretty crazy, thanks for sharing, Jeff.&lt;p&gt;Overclocking was my bread and butter as a [relatively] broke teenager in the late nineties, around the era of the first Athlon Thunderbirds, when you could take a 1GHz chip and [maybe] OC it to 1.5Ghz.  It was a great time to be alive, and yet this is the first case I&amp;#x27;ve heard of where LN2 would not give you a dramatically better result 99.99%+ of the time! I still miss HardOCP and Kyle Bennett and his team&amp;#x27;s reviews.&lt;p&gt;That one t-bird with char spots... It still worked reliably somehow, I might even have it in a box somewhere.  Those swirly finned CPU coolers were shit!  I came home every day after school and volted&amp;#x2F;burned the hell out of that poor chip, not realizing what I was doing.. lol.</text></item><item><author>geerlingguy</author><text>No physics-level explanation, just that they found the chips to be more stable in testing when they were a little warmer vs a little colder. The key was to keep them around that temperature, though, which still requires a good amount of cooling the more voltage that runs through it!&lt;p&gt;Just... he mentioned I might not have as much success using LN2 or something more exotic, compared to standard water or Peltier cooling.</text></item><item><author>metadat</author><text>Did the engineer explain why the higher temps contribute to stability?  I&amp;#x27;ve not heard of such a phenomenon before.</text></item><item><author>geerlingguy</author><text>Awesome work, and I&amp;#x27;m glad you could post some results! I&amp;#x27;m hoping to get time to delid one, put on a peltier cooler, and try to control the temperature a little better for a run to see how high it&amp;#x27;ll go before either burning up or going unstable.&lt;p&gt;From my testing on clocks on the Pi 5, it looks like the default clock of 2.4 GHz is pretty close to the sweet spot for this chip (BCM2712), and you burn a lot of power for small incremental gains after that[1]. (Which you seem to also show with the 3.3 GHz overclock!).&lt;p&gt;I also spoke to one of the Pi engineers about the chip behavior at higher clocks, and he suggested unlike some chips, this chip might run more stably at higher temperatures (like 50-60°C) rather than &amp;#x27;as cold as you can get it&amp;#x27;. So that poses some challenges since most cooling solutions aren&amp;#x27;t tuned for &amp;#x27;keep a temperature&amp;#x27; but instead &amp;#x27;get it as cold as possible&amp;#x27;, without a lot of manual tweaking.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.jeffgeerling.com&amp;#x2F;blog&amp;#x2F;2023&amp;#x2F;overclocking-and-underclocking-raspberry-pi-5&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.jeffgeerling.com&amp;#x2F;blog&amp;#x2F;2023&amp;#x2F;overclocking-and-unde...&lt;/a&gt;</text></item></parent_chain><comment><author>bayindirh</author><text>I have overclocked a 1433MHz Athlon 1700+ (TBred&amp;#x2F;B IIRC) to 2200 MHz (3200+ levels) with an AN7-Ultra.&lt;p&gt;The secret sauce was running it at 200x11, with 1T capable RAMs, and that thing was snappier than &amp;quot;bog standard&amp;quot; 3200+ systems a considerable amount.&lt;p&gt;Without much of a voltage bump, and a good cooling solution, it ran within its thermal design without noise, and with rock solid stability. That system lived more than 15 years IIRC.</text></comment>
<story><title>Beating Jeff&apos;s 3.14 Ghz Raspberry Pi 5</title><url>https://jonatron.github.io/randomstuff/pivolt/</url></story><parent_chain><item><author>K0balt</author><text>I still remember my dual celeron 450 clocked to 900 mhz.  Those chips ran rock solid at double their rated clock, no didling the voltage or anything.  Just needed decent cooling.  Never mind that at the time having 2 processors was nearly useless.</text></item><item><author>metadat</author><text>That&amp;#x27;s pretty crazy, thanks for sharing, Jeff.&lt;p&gt;Overclocking was my bread and butter as a [relatively] broke teenager in the late nineties, around the era of the first Athlon Thunderbirds, when you could take a 1GHz chip and [maybe] OC it to 1.5Ghz.  It was a great time to be alive, and yet this is the first case I&amp;#x27;ve heard of where LN2 would not give you a dramatically better result 99.99%+ of the time! I still miss HardOCP and Kyle Bennett and his team&amp;#x27;s reviews.&lt;p&gt;That one t-bird with char spots... It still worked reliably somehow, I might even have it in a box somewhere.  Those swirly finned CPU coolers were shit!  I came home every day after school and volted&amp;#x2F;burned the hell out of that poor chip, not realizing what I was doing.. lol.</text></item><item><author>geerlingguy</author><text>No physics-level explanation, just that they found the chips to be more stable in testing when they were a little warmer vs a little colder. The key was to keep them around that temperature, though, which still requires a good amount of cooling the more voltage that runs through it!&lt;p&gt;Just... he mentioned I might not have as much success using LN2 or something more exotic, compared to standard water or Peltier cooling.</text></item><item><author>metadat</author><text>Did the engineer explain why the higher temps contribute to stability?  I&amp;#x27;ve not heard of such a phenomenon before.</text></item><item><author>geerlingguy</author><text>Awesome work, and I&amp;#x27;m glad you could post some results! I&amp;#x27;m hoping to get time to delid one, put on a peltier cooler, and try to control the temperature a little better for a run to see how high it&amp;#x27;ll go before either burning up or going unstable.&lt;p&gt;From my testing on clocks on the Pi 5, it looks like the default clock of 2.4 GHz is pretty close to the sweet spot for this chip (BCM2712), and you burn a lot of power for small incremental gains after that[1]. (Which you seem to also show with the 3.3 GHz overclock!).&lt;p&gt;I also spoke to one of the Pi engineers about the chip behavior at higher clocks, and he suggested unlike some chips, this chip might run more stably at higher temperatures (like 50-60°C) rather than &amp;#x27;as cold as you can get it&amp;#x27;. So that poses some challenges since most cooling solutions aren&amp;#x27;t tuned for &amp;#x27;keep a temperature&amp;#x27; but instead &amp;#x27;get it as cold as possible&amp;#x27;, without a lot of manual tweaking.&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.jeffgeerling.com&amp;#x2F;blog&amp;#x2F;2023&amp;#x2F;overclocking-and-underclocking-raspberry-pi-5&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.jeffgeerling.com&amp;#x2F;blog&amp;#x2F;2023&amp;#x2F;overclocking-and-unde...&lt;/a&gt;</text></item></parent_chain><comment><author>geerlingguy</author><text>Heh, back in those days decent cooling was a lot easier than now (for overclocking, at least).&lt;p&gt;That&amp;#x27;s one nice thing working on these little mobile chips—I don&amp;#x27;t need a $300 cooler, I can use a cheap little water block, or a small peltier element that doesn&amp;#x27;t cost much at all... and it&amp;#x27;s not being a space heater for the room. It&amp;#x27;s only pulling maybe 10-20W max.</text></comment>