Chihiro type3 stopped working/turned off - 2 status lights (green/red) are not on.

[obcd]

That's true, but it's very difficult to separate the heatsink from the gpu after so many years.
The original thermal paste becomes very hard.
Besides that, it's also difficult to find a good heatsink and proper clamp to mount it, unless you sacrify an xbox motherboard for it.

I always thought the smaller heatsink + fan was giving lower temperature readings and sega choose that option because of it. Let's not forget that a chihiro runs games in demo for long hours, so the gpu load is much higher than it is with a normal xbox. Recently, I did some tests that showed nearly identical temperature readings with the small heatsink + fan and the bigger heatsink. I still want to test a bit more before I will say a 1.1+ heatsink performs equal well to a 1.0 heatsink with a fan.

A better solution would be if the kernel would monitor the gpu and cpu temperature and shut the system down when it overheats.

Even naomi does a better job there and refuses to start when a fan isn't spinning.

 

[GravitySandwich]

That's true, but it's very difficult to separate the heatsink from the gpu after so many years.
The original thermal paste becomes very hard.
Besides that, it's also difficult to find a good heatsink and proper clamp to mount it, unless you sacrify an xbox motherboard for it.

I always thought the smaller heatsink + fan was giving lower temperature readings and sega choose that option because of it. Let's not forget that a chihiro runs games in demo for long hours, so the gpu load is much higher than it is with a normal xbox. Recently, I did some tests that showed nearly identical temperature readings with the small heatsink + fan and the bigger heatsink. I still want to test a bit more before I will say a 1.1+ heatsink performs equal well to a 1.0 heatsink with a fan.

A better solution would be if the kernel would monitor the gpu and cpu temperature and shut the system down when it overheats.

Even naomi does a better job there and refuses to start when a fan isn't spinning.

The plus point of the bigger heatsink is that the fan on it can't fail, because it ain't there. I am with you on the hard thermal paste though. I've been an xbox classic modder for ages and sometimes those bastards won't come off at all. Warming up the heatsink to 50c makes them come loose a lot easier. About the 24h demo mode. One of my xboxes runs virtua cop 3 in an arcade cabinet(Chihiro was defective, and to expensive for me to replace at the time). It's not getting any hotter than it would idling on dashboard. So i see temps that are around 45-50c with the big heatsink. i did replace the fan last year to a noctua 80mm to make sure that the old fan wouldn't die on me though. After that it even ran cooler.