Overclocking Pi 3

jay81uk

Does this actually give a performance boost for consoles such as the N64 or PSP emulator?

I know there's an option in the menu to overclock with a few different settings, so what do you think is the best one for emulation? Note, I haven't got my heatsink yet but I can easily take the lid off my Pi 3's case to give it some air - is that enough?

Thanks

cyperghost

You can overclock with a speed win of 10 to 15%. But keep a look to the CPU core temparature. Even not overclocked the Pi3 is a hot thing :)
But there is in no way the same potential as for the RPi2!

CPU-Temperatur
in °C 	Pi3B    Pi2B 	Pi2B(OC) Pi1B RPi1(OC)
Idle: 	 40      37 	 37 	  43   	44
Usage: 	 82      54 	 57 	  46  	52

sourece:
https://willy-tech.de/raspberry-pi-3-leistung-im-vergleich/#CPU-Temperatur

jay81uk

Doesn't seem much point in overclocking then? I have no idea how to monitor temperatures.. I'm new to this...

cyperghost

You can overclock from 1,2GHz to 1,4GHz (works in some cases)... but imho it isn't a "must have".

The Pi2 was easier to overclock from 0,9GHz to 1,1GHz (very stable run) in most cases 1,2GHz were also no problem to reach. The temperature increase was not a big part to deal with :)

http://www.jackenhack.com/raspberry-pi-3-overclocking/

RetroResolution

Generally, overclocking really gives a usable boost to the more complex emulators - the N64 and Dreamcast notably (for the latter, in testing it's the GPU overclock that really helps this emulator).

As I record audio/video from the RetroArch emulator cores directly on my Pi, overclocking really helps with this too.

For the other emulators, if you're using shaders to give an enhanced retro feel to the visuals, overclocking may be needed as adding the graphical effects puts a strain on the system (depending on which shader is used)

RetroResolution

@jay81uk I've written various guides on overclocking/testing the Pi 2 and Pi 3, including the temperature issues - if you search my posts you'll find them, or visit retroresolution.com

jay81uk

I will be using N64 on my Pi so I guess overclocking is important then.

A real shame Silent Hill PSP doesn't work apparently.

RetroResolution

@jay81uk keep in mind that the n64 is a very difficult machine to emulate, due to the option developers had of writing custom microcode for the GPU. Some games really fly even on a Pi 2 (Mario 64...), whereas others are unplayable on an overclocked Pi 3, or plain just don't work.

There is a compatibility list spreadsheet (I don't have the link to hand, but search the forum and you'll find it).

The N64 Retroarch core generally hampers everything, so you're best off using the mupen64plus non-retroarch version. Then it's a question of picking the optimal n64 'core' to use for a given title.

Again, searching the forum should unearth some detailed discussions on all thus.

I keep meaning to write up a guide, but never quite make it...

jay81uk

I just watched this video -

It seems simple to overclock. He has scared me though saying he's not responsible if the Pi explodes?!

I have some heatsinks arriving soon. Currently, Zelda on N64 does slightly lag. Is overclocking the Pi going to make Zelda fly like Mario 64 and Mario Kart does, or is it just not worth it?

Thanks

RetroResolution

@jay81uk hi,
Regarding overclocking, you should be fine provided you don't override/turn off the Governor, which dynamically adjusts the clock speeds based on demand and temperature.

Further details can be found on the following discussion threads:

https://retropie.org.uk/forum/topic/2257/overclocking
(Mainly, the final post in this thread)

https://retropie.org.uk/forum/topic/2597/pi3-overclocking-overheating-issues

cyperghost

@RetroResolution said in Overclocking Pi 3:

@jay81uk I've written various guides on overclocking/testing the Pi 2 and Pi 3, including the temperature issues - if you search my posts you'll find them, or visit retroresolution.com

Thx Retro - I took your page to my RPi favourites

RetroResolution

@cyperghost great, glad to help!

jay81uk

I don't think the video above means the 'governer' is changed at all. Could someone check if the instructions in that video are ok please?

bazmonkey

@jay81uk said in Overclocking Pi 3:

I don't think the video above means the 'governer' is changed at all. Could someone check if the instructions in that video are ok please?

That's correct, I didn't see anything in there about adjusting the governor.

To be precise, the governor doesn't necessarily adjust the clock speed dynamically. Certain governors (like 'ondemand') do, but others (such as 'performance' or 'powersave') blindly run at a set frequency (the maximum in the case of 'performance').

Temperature-triggered throttling is done by a separate mechanism. You don't want to adjust this for safety. The CPU frequency governors are load-based (e.g. ondemand raises clockspeed if it can and if it sits at 95%+ load).

You can also set the governor when you start an emulator (I forget off-hand where the option is). "ondemand" is great most of the time, but when I play a game, I don't want it to pause before ramping up. I'd rather have it run whole-hog until the game finishes.

jay81uk

Wow... I'm not even overclocking and I got the warning square just playing a NES game!

I've got the official red/white case with no heatsink at the moment. However from what I've read, even with a heatsink, this case is like an oven....

bazmonkey

@jay81uk Are you sure you're not seeing the rainbow-colored warning square, or is it yellow-to-red colored? Even sealed in a box I can't imagine a Pi overheating on a NES game.

jay81uk

No it's a dark yellow coloured box.

bazmonkey

Bummer. If you're in the market, you can get a great layered case / heatsinks / fan for like $8 on eBay. It's not the quietest, but I couldn't overheat it if I tried.

jay81uk

Just find it weird it happened on a NES game! I'll have to add a heatsink and take the lid off when playing I guess.

Or get the flirc case.

bazmonkey

@jay81uk You may find that simply removing the cover is sufficient.