Overclocking computer systems is a fun way to extract some free performance, or at least see how far you can push the hardware before you run into practical limitations. The newly released Raspberry Pi 5 with BCM2712 SoC is no exception here, with Tom’s Hardware having a go at seeing how far both the CPU and GPU in the SoC can be pushed. The BCM2712’s quad Cortex-A76 CPU is normally clocked at 2.4 GHz and the VideoCore VII GPU at 800 MHz. By modifying some settings in the
/boot/config.txt configuration file these values can be adjusted.
In order to verify that an overclock was stable, the Stressberry application was used, which fully loads the CPU cores. Here something like a combination of stress-ng and glxgears could also be used, to stress both the CPU and GPU. With the official actively cooled heatsink the CPU reached a temperature of 74°C with a whole board power usage of about 10 Watts. At idle this dropped to 3 Watts at 46°C. At these speeds, the multiple Raspberry Pi 5 units OCed by Tom’s Hardware were mostly stable, though one of the team’s boards experienced a few crashes. This suggests that this level of OCing could still be subject to luck of the draw, and long-term stability would have to be investigated as well.
As for the practical use cases of OCing your Raspberry Pi 5, benchmarks showed a marked uplift in compression and Sysbench benchmark scores, but OCing the GPU had no real positive impact on YouTube or 3D performance, leading even to a massive increase in dropped frames with video playback. This probably means that increasing the CPU clock may be beneficial, but OCing the GPU could be futile without also OCing the RAM frequency, if at all possible.
Realistically, the Raspberry Pi SoCs never were speed monsters, with even the Raspberry Pi 4B’s SoC being beaten handily in 2020 by a budget dual-core Intel CPU. The current Intel Alder-Lake-N-based N100 SoC has a 6 Watt TDP and boosts up to 3.4 GHz while its Xe-LP-based iGPU (with AV1 decoding support) makes for a decent gaming experience within a ~16 Watt power envelope. Clearly, any OCing of the Raspberry Pi boards is more for the challenge of it, but then so is running the latest Intel CPU at 10 GHz with liquid nitrogen cooling.
It’s not news that EVGA is getting out of the GPU card game, after a ‘little falling out’ with Nvidia. It’s sad news nonetheless, as this enthusiastic band of hardware hackers has a solid following in certain overclocking and custom PC circles. The Games Nexus gang decided to fly over to meet up with the EVGA team in Zhonghe, Taiwan, and follow them around a bit as they tried for one last overclocking record on the latest (unreleased, GTX4090-based) GPU card. As you will note early on in the video, things didn’t go smoothly, with their hand-lapped GPU burning out the PCB after a small setup error. Continue reading “The Tale Of The Final EVGA GPU Overclocking Record”
How fast can a Raspberry Pi Pico go? Well, apparently the answer is 1 GHz if you freeze it and give it over twice the voltage it normally gets. Oh, one catch. After a few minutes, the chip will fry itself.
That’s the results reported by [David] who took a Peltier cooler and a pretty serious over-voltage. The dhrystone scores went from around 200 to over 1100. Of course, there’s that pesky early death to worry about, so you probably won’t want to try this at home.
Even before the chip bites the dust, there are other problems to address. For example, once you get much over 250 MHz, the Pico’s SPI flash can’t keep up, so all the software you want to run has to be put in RAM first. You’ll also want to do some poking at the system clock parameters.
Honestly, we enjoy overclocking PCs or just about anything else. The good news is if you fry a Pico, it won’t make a sizable dent in your wallet. It is also a fun way to learn a bit more about the internals of the processor. According to [David], the cooler took the part to -40 C. We wonder how it would fare in a bath of LN2?
Of course, you can push a regular Pi, too. If you really need a 1 GHz overclocked microcontroller, maybe check out the Teensy.
We never insist that a hack be practical. [Tech Ingredients] is living proof as they modded a computer case to use a window air conditioner for overclocking a computer. They think they haven’t hit the ceiling yet, and got their AMD Ryzen 8-core processor up to 4.58 GHz.
An advantage of forcing air from an air conditioner is that the air forced into the system is quite dry and clean. The trick is to create a simple duct to attach to a 5,000 BTU air conditioner. It doesn’t actually interface with the CPU cooling block, instead it just forces cool air into the case and this tends to cool everything inside. Admittedly, it isn’t any worse than plunging your computer in liquid nitrogen, and we’ll admit that air conditioning units are made to keep large areas cold and work at high duty cycles. With the air conditioning running, they disconnected at least some of the stock fans. The temperatures stayed cool even at high speeds.
Continue reading “PC Overclocking With An Air Conditioner”
There are three different versions of the Raspberry Pi 4 out on the market right now: the “normal” Pi 4 Model B, the Compute Module 4, and the just-released Raspberry Pi 400 computer-in-a-keyboard. They’re all riffing on the same tune, but there are enough differences among them that you might be richer for the choice.
The Pi 4B is easiest to integrate into projects, the CM4 is easiest to break out all the system’s features if you’re designing your own PCB, and the Pi 400 is seemingly aimed at the consumer market, but it has a dark secret: it’s an overclocking monster capable of running full-out at 2.15 GHz indefinitely in its stock configuration.
In retrospect, there were hints dropped everywhere. The system-on-a-chip that runs the show on the Model B is a Broadcom 2711ZPKFSB06B0T, while the SOC on the CM4 and Pi 400 is a 2711ZPKFSB06C0T. If you squint just right, you can make out the revision change from “B” to “C”. And in the CM4 datasheet, there’s a throwaway sentence about it running more efficiently than the Model B. And when I looked inside the Pi 400, there was this giant aluminum heat spreader attached to the SOC, presumably to keep it from overheating within the tight keyboard case. But there was one more clue: the Pi 400 comes clocked by default at 1.8 GHz, instead of 1.5 GHz for the other two, which are sold without a heat-sink.
Can the CM4 keep up with the Pi 400 with a little added aluminum? Will the newer siblings leave the Pi 4 Model B in the dust? Time to play a little overclocking!
Continue reading “Adventures In Overclocking: Which Raspberry Pi 4 Flavor Is Fastest?”
CPUs generate their heat in the silicon die that does all those wonderful calculations which make our computers work. But silicon conducts heat fairly poorly, so the thinner your CPU die, the better it will conduct heat out to the heatsink. This theoretically promises better cooling and thus more scope for performance. Thus, it follows that some overclockers have taken to lapping down their CPU dies to try and make a performance gain.
It’s not a simple process, as the team at [Linus Tech Tips] found out. First, the CPU must be decapped, which on the Intel chip in question requires heating to release the intermediate heat spreader. A special jig is also required to do the job accurately. Once the bare CPU is cleaned of all residual glue and heat compounds, it can then be delicately lapped with a second jig designed to avoid over-sanding the CPU.
After much delicate disassembly, lapping, and reassembly, the CPU appears to drop 3-4 degrees C in benchmarks. In overclocking terms, that’s not a whole lot. While the process is risky and complicated for little gain, the underlying premise has merit – Intel thinned things out in later chips to make minor gains themselves. Video after the break.
Continue reading “Die Lapping For Better CPU Performance”
The bsnes emulator has a new overclocking mode to eliminate slowdowns in SNES games while keeping the gameplay speed accurate. We’re emulating old SNES hardware on modern machines that are vastly more powerful. Eliminating slowdowns should be trivial, right? For an emulator such as bsnes, which is written to achieve essentially pixel-perfect accuracy when emulating, the problem is decidedly non-trivial. Stick around to learn why.
Continue reading “Overclocking In An SNES Emulator”