G4 cube an Sonnet Encore ST Duet G4

[Cktwo]

Hey guys,

I managed to obtain a Sonnet Encore ST Duet G4 1.8 GHz which I want to use in my G4 cube. The Cube until now was equipped with a (non Duet) Sonnet Encore ST G4 1.8 GHz, an Artmix VRM etc. and ran fine with this. The Duet however doesn't want to boot. Of course, I have installed the latest Firmware update from the Sonnet website (which seems to be the same for all Sonnet Encores, dated May-08-19) and reset the PRAM after the installation. However, I don't get a picture.

This is the card:


Any ideas what could be wrong? I doubt that it doesn't run at all in the G4 cube. I probably would fail if I hadn't upgraded the VRM, PSU etc. but I have done all that.

Thanks and kind regards
CK

P.S.: Yes, the Cube is equipped with LOTS of additional cooling, so it shouldn't overheat.

 

[macuserman]

What kind of heatsink are you using/how is it being held in place? Is it possible that it is not staying seated correctly after being installed? I'm not sure how you are securing it, but that could be part of your issue.

 

[Cktwo]

I am using the original G4 cubes heatsink which I have widened to fit the dual G4. One fan is blowing from below, another one is blowing straight on the heaksink.

Meanwhile I have managed to start the booting process. However, the system freezes in the middle of the boot process (the Apple logo appears, the spinning boot wheel as well) and the it freezes.

Very weird. Any ideas what I could do to do further diagnostics? I can enter OpenFirmware and it seems to be stable there.

Thanks!

 

[herd]

Is this the same Cube that wouldn't work with the Sonnet "1.2"? What was the problem there?

Without much to go on, I would guess it's a power supply problem. What are the voltages at the CPU? Does the Dual work in a different machine? Does the Cube work with a different CPU? You could lower the speed/voltage on the Dual to see if that helps. etc...

 

[Cktwo]

The Cube works fine with both a Sonnet Encore G4 1.2 GHz and a Sonnet Encore G4 1.8 GHz. I have been using the latter (which fans for cooling of course) for quite a while.

How can voltage/speed be reduced in the Cube?

Thanks!

 

[herd]

Speed/voltage are configured with resistors on the Sonnet PCB.

68kmla.org/bb/index.php?threads/overclocking-the-sonnet-encore-st-g4.38487/

 

[Cktwo]

Thank you!