For about a minute, maybeNow we can run PS2 emulator full speed on Pyra!
While it's good news on it's own, it bring back the sad truth that it simply won't be possible to 100% the CPU for an extended period of time. I know this handcrafted test to stress the CPU to the fullest extend, but for purposes like longer time 2 thread compiling or really well optimized software:
What is the clock speed where the OMAP5 doesn't reach critical temperatures at all? The planned cooling stuff will only postpone the emergency downclock, so I think it may be better to avoid that stage if possible. For demanding games you'd probably also rather want consistent performances instead of random drops.
I would be ecstatic to see even just the PS2 starting logo slowly appearing on Pyra for about a minute.For about a minute, maybe
Yes, it is without any special thermal measures. It is more to see if the CPU runs at all at higher clock.@hns - What are you running for simulating stress? I've used the stress command with a varying number of CPU hogs enabled and don't get the high temperatures you seem to get on the EVM.
@elvissteinjr - We can't yet say how real life CPU load behaves, I'm not sure if they've even played with applying thermal pads/paste yet to help it dump the heat to the PCB.
Hmm that's the old loop derived from pandora's CPU stress test, which isn't doing that much really. You should be using the later one that I tried to tune for Cortex-A15 specifically, which also checks if calculations are correct. Here it is again:
No, production of the new boards has just started. I think the last prototypes are from November. This could imply that the cause was not power delivery related after all.Edit: Or maybe I'm just forgetting who's got what. Perhaps hns and zmatt have got boards with the new vias.
*speculating speculating speculating*
The heat pad that connects the SoC to the PCB (which has copper layers for cooling) is also not yet installed and an aluminium plate will be installed as well behind the SoC.
I don't have a reference right now, but ED said a long time ago that the cooling solution for the SoC would connect to the SD cages. This makes some sort of heat sink necessary and while he's at it it would only make sense to expand it over as much of the footprint of the Pyra as possible.I'm assuming that since the plate would rest between the SoC board and the case plastics that it would have been taken into account in the mold generation. Does it connect over to the SD cages?
Don't fill that corner - it's where the longer RHS extends into. (Red Hot Stylus - side experiments of mine.)I'm not sure how well that would work, but it might even be worth considering to put some larger heat sink element in the empty lower front left corner.
Since the plastic case would still block the heat dissipation I'm not sure if it would be better to design it like a traditional heat sink with a lot of surface area, or if a solid block of aluminium would make more sense, so it would be more of an actual heat sink to absorb thermal peaks instead of a heat dissipator.