When/Why Did MiSTer Start Running DE10 So Hot?

[bankshot]

I have built and used MiSTer for past few years and thoroughly enjoyed. So much, that I converted my original fan-based version MiSTer to a fanless case from a reputable vendor, and built another as a backup.

They always ran cool to the touch, except for certain tough cores like the Cave arcade shmups, which would get quite warm. They are more modern and intensive so no problem, this was understood.

So I am playing routine things lately and my case is super warm to the touch on things that it never was. Always hot on old arcade cores, NES core. I found an older SD card MiSTer brain I had as a backup that has not been updated in quite some time and when I plugged it in and used it my suspicions were correct...the system was running cooler on these same old things. What is going on????

[aberu]

Well there's a few things going on there...

1. Hot to the touch is a function of the thermal conductivity of the material and how fast it can transfer heat to your fingers. Aluminum is a very good thermal conductor. So a minor change in temperature may be more apparent.

2. There has been more added to the framework and more added to the Main MiSTer binary (which runs on the ARM side) over the past couple years, including a use of some more DSP's, so this may be having an impact somewhat.

3. This is a colder time of year maybe in your region, so the relative temperature difference might make it so you are noticing the difference more strongly.

The case being hot isn't necessarily a bad thing since that whole case is a heatsink. I wouldn't get too dramatic.

[Armakuni]

The whole case is acting as a passive heatsink so is expected

[bankshot]

Thanks birdybro!

Just to clarify in case I did not do a good job of explaining, I now have two MiSTers in fanless cases (nicknamed "Prod" and "Dev" for those who can appreciate the IT humor) and they both exhibit the same warmer issue now. I have always ran them in stock kernel configuration.

The weather is very nice where I am at, short-sleeves/shorts conditions. Based on your post, I suspect that your bullet point #2 is the accurate explanation for the conditions I am now experiencing. As has been mentioned, yes it is good to know that the case is doing a great job being an efficient heatsink by having good thermal conductivity to the processor. It is amazing to me that a modern processor like this can have such a high heat tolerance even without a heatsink or fan and not burn itself up to a crisp like the old Intel/AMD CPUs had no problem doing to themselves.

Thanks again.

[aberu]

The rated operating temperature of the cyclone v soc on the de10-nano is -40°C ~ 100°C, it's the automotive rated chip. It should be fine.

[Mr. Encyclopedia]

I've heard a lot of stories about people ruining their DE10-Nano over the years but can't think of an example of one overheating to the point of failure. As Aberu said, the chips it uses are rated for much harsher environments than we subject them to, so I don't think it's cause for alarm.