Avg. N64 Temps. Or, how much heatsink do I really need?

[Mario]

I originally asked how hot the N64 gets under normal operating conditions. I got some excellent information. I added the temperatures in Fahrenheit. Thanks to Daftmike, Marshallh, and Zeturi.

With an 18°C (64°F) ambient temp, running the 3.3V line at 3.05V, after 45 mins of 8 bot perfect dark multiplayer without heatsinks, in free air, my rcp was at 64°C (147°F), the memory at 60°C (140°F), and the cpu at 49°C (120°F).

I didn't test until the system shut down but the temps had stabilised after 45 mins, in a typical n64p volume case, you are looking at at least 20°C (68°F) above ambient and I would recommend keeping the package temps below 85°C (185°F).

When I did my testing there were no crashes for four hours with a slight under-volt (3.05V) and no heatsinks, the temperatures levelled out after 45 mins.

Theoretically to keep the chips under 80°c (176°F), inside a case, I estimate your heatsinks would need only about 12°C (54°F)/W thermal resistance. This is relatively modest, most pc ramsinks should be more than suitable with a little airflow.

My dev 64 has been run for hours at a time with no heatsink, just the aluminum blocks on each chip. They get pretty hot but the N64 never shut down or started to crash.

I took a record of the heat coming off the n64 for a couple of hours:

38 PM started test,
CPU: 30
RCP: 32
RAM: 32

4:04 PM
CPU: 45.5
RCP: 51
RAM: 48.5

41 PM
CPU: 51
RCP: 53
RAM: 50

5:00 PM
CPU: 52
RCP: 53.5
RAM: 50

5:13 P.M. Ended test,
CPU: 50
RCP: 53.5
RAM: 52

Looks like my temps won't climb beyond these last recorded ones. (Though possible +20 more degrees while in the case.)

I do have another n64, I hooked it up to my TV and let it run without heat sinks. I got bored after 20 minutes, because the temps never got high, really. Here's what I got:

CPU: 43
RCP: 45
RAM: 50

Granted, it only ran for 20 minutes, but the numbers didn't climb any higher than these. Usually they were about 4 degrees lower. The heat is almost the same as when I had heat sinks! Though the heat might climb a bit more over time, with heat sinks like what I used, I doubt temperatures would increase much. (But will increase once inside a case.) The revision of the board I just tested is 3, and the revision that I've already messed with is a Revision 8. With a small fan installed, there would be little to no heat.

Graph of Zeturi's Test:

The N64 really needs a lot less heatsinking than was thought before. I think the wrong assumption came from how big the N64's stock heatsink is. It's like the shielding - it's not necessary, but they have to put it there anyway.

 

[βeta]

Re: How hot does the N64 get?

You really don't need a fan. Save yourself the trouble.

 

[Mario]

Re: How hot does the N64 get?

It's for my already-completed Retro64, and it does need a fan.

 

[βeta]

Re: How hot does the N64 get?

What kind of heat-sinkage do you have?

 

[Mako321]

Re: How hot does the N64 get?

why don't you just get back to work on the sprocket64?

 

[Mario]

Re: How hot does the N64 get?

What kind of heat-sinkage do you have?

4-mm high VGA RAM heatsinks. Finned, but not quite enough cooling in a compact, wire-stuffed case.

why don't you just get back to work on the sprocket64?

'Cause I don't feeeeel like it.

I want to finish up some things on my first N64 portable first. Besides, I'm having trouble with the c-button joystick. It seems that only works on 1st party n64 controllers and I have to build some kind of circuit to get it to work on my 3rd party one.

 

[Mako321]

Re: How hot does the N64 get?

What kind of heat-sinkage do you have?

4-mm high VGA RAM heatsinks. Finned, but not quite enough cooling in a compact, wire-stuffed case.

why don't you just get back to work on the sprocket64?

'Cause I don't feeeeel like it.

grim adventures of billy and mandy: BEST SHOW EVER.

 

[snowpenguin]

Re: How hot does the N64 get?

...What.

 

[Mario]

Re: How hot does the N64 get?

Okay. That wasn't a reference, though.

Temperatures plz. Celsius or Fahrenheit is fine.

 

[βeta]

Re: How hot does the N64 get?

I don't have an infrared thermometer. Go buy one, use it, return it.

 

[daftmike]

Re: How hot does the N64 get?

With an 18°C ambient temp, running the 3.3V line at 3.05V, after 45 mins of 8 bot perfect dark multiplayer without heatsinks, in free air, my rcp was at 64°C, the memory at 60°C, and the cpu at 49°C.

I didn't test until the system shut down but the temps had stabilised after 45 mins, in a typical n64p volume case, you are looking at at least 20°C above ambient and I would recommend keeping the package temps below 85°C.

 

[βeta]

Re: How hot does the N64 get?

How little heat dispersion is required to keep it at 80ºC?

 

[Mario]

Re: How hot does the N64 get?

With an 18°C ambient temp, running the 3.3V line at 3.05V, after 45 mins of 8 bot perfect dark multiplayer without heatsinks, in free air, my rcp was at 64°C, the memory at 60°C, and the cpu at 49°C.

I didn't test until the system shut down but the temps had stabilised after 45 mins, in a typical n64p volume case, you are looking at at least 20°C above ambient and I would recommend keeping the package temps below 85°C.

Excellent, daftmike. Thank you very much!

85 C is 185 F - that's crazy hot! I think I'll make the fan go on at 75 C.

So, are you saying that without heatsinks the N64 ran for at least 45 minutes? (in open air, 18 C ambient). It didn't crash?

 

[Mako321]

Re: How hot does the N64 get?

are you using a TI thermostat or something?

 

[daftmike]

Re: How hot does the N64 get?

When I did my testing there were no crashes for four hours with a slight under-volt (3.05V) and no heatsinks, the temperatures levelled out after 45 mins.

Theoretically to keep the chips under 80°c, inside a case, I estimate your heatsinks would need only about 12°C/W thermal resistance. This is relatively modest, most pc ramsinks should be more than suitable with a little airflow.

 

[hailrazer]

Re: How hot does the N64 get?

Was that with 12v or 7.4v on the 12v line?

 

[βeta]

Re: How hot does the N64 get?

What's that meant if you're using a flat sheet of copper?

 

[daftmike]

Re: How hot does the N64 get?

I ran 7.4V through the 12V line, using 12V instead of 7.4V would not greatly affect the main chip temps, but it might perhaps raise the case temps by 5-10°C (theoretically).

Roughly, I would guess a copper sheeet of 2mm thickness and 120X120mm should be fine to cool the all the chips on the n64 below 80°C, but this is only theory, you should do your own testing to find what works in your case.

 

[Mario]

Re: How hot does the N64 get?

are you using a TI thermostat or something?

No, it's actually by Microchip Technologies. Here it is on Mouser:
http://mouser.com/ProductDetail/Microch ... M1RMbC8%3d

You set the temperature by a resistor. It has two outputs: one normally low, and one normally high. When it gets above the set temperature, it flips both outputs.

Daftmike, this is very useful information. Do you mind if I quote it or put it in the sticky?

 

[daftmike]

Re: How hot does the N64 get?

I don't mind at all, but I can't guarantee anyone else will get the same results.