I Bought a Better System Board for my Octane and Need Troubleshooting Help

jdmcs

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First time SGI owner here with no previous experience with the platform... seems like I am jumping in head first as they say.
I picked up an SGI Octane from a swap meet a couple weekends ago. It was the base model, but hey, I paid $75.
I then found an IP30 030-0887-005 system board on Mercari, and the seller of that board sent me an offer for $70. I couldn't resist having the 400MHz processor, plus whatever RAM was on the system board, for the bargain price.
The board arrived yesterday, and I went to swap out my board for the new system board. When I plugged the machine back in, I heard two relays clicking but nothing else happened (no fans, no lights except for an internal one that briefly flashes).
I swapped my board back in, plugged it back in, and the Octane powered up.
I then proceeded to swap between both boards, hoping the dance would result in both boards working. However, even after many attempts to reseat the new board, then swapping back to my board to make sure I had not done worse to the Octane, the behavior stays the same. My system board allows the system to power up, and the new system board results in two relays clicking and that's it.
Is there anything I've overlooked?
 

jdmcs

TinkerDifferent Board DoP&G
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I thought I should add some photos in case someone spits something that is amiss…

Here’s my system model number, a CMNB015ANF250 (it’s one of the “green” Octanes):
IMG_6722.jpeg
And the part number of the new system board:
IMG_6721.jpeg
Here’s one of the compression connectors from two angles:
IMG_6716.jpegIMG_6719.jpeg
And the other:
IMG_6717.jpegIMG_6720.jpeg
And how these compression connectors work is beyond me… I’m just a geek that enjoys exploring old computers. 🤓
 
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ScutBoy

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Wow - you did your Octane way cheaper than me! :)

From a quick look, it don't see why that board wouldn't work, unless it needs a different backplane version.

Are you able to swap over just the CPU module from the new board to the working board? If you have pics of both boards it might help.
 
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ScutBoy

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Do you get any kind of light at the lightbar when you turn it on? Usually starts out white, then turns red until initial diags pass.

This assumes the bulbs in your light bar are not burned out, which can be very likely...
 

jdmcs

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Do you get any kind of light at the lightbar when you turn it on? Usually starts out white, then turns red until initial diags pass.

This assumes the bulbs in your light bar are not burned out, which can be very likely...
With my original system board, the light bar is red (the white light could be burned out… did SGI use bulbs and not LEDs?). With the new system board, I never see any lights.
 

ScutBoy

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I'd swap CPU module from the one board to the other at this point...

Yes - the lightbar uses incandescent bulbs, and they often are burnt out at this point. There are pointers on-line on how to replace the bulb or "upgrade" to an LED.
 

ClassicHasClass

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I have to say that I've always found the Octanes to be a bit of a bag of hurt (along with their contemporary the O2). There are things to dislike about the Fuel but it's relatively straightforward to work on.
 

ScutBoy

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I agree that SGI machines seem to be much more fiddly in both hardware and software from their contemporary Sun counterparts, but this might be partly due to the fact that I spend a lot of time with Suns back in the day. Even so, in the last month I've brought back to life two Octanes, a R4K Indigo, and an Indy, and each had their hardware or IRIX struggles. That said, it's been kind of a fun challenge.

I have left an R3K Indigo that sometimes posts. If it does, it quickly crashes with a "CPU Parity" error. In most cases, it immediately fails POST with a "Replace CPU board" message. The bonus problem with this is that I have an Indigo Elan graphics board, but the machine wont boot at all with that in. Any progress I've made has been using the base LG1 graphics board. Once I get the machine to reliably boot, then I can worry about the ELAN...
 

ScutBoy

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I agree that SGI machines seem to be much more fiddly in both hardware and software from their contemporary Sun counterparts, but this might be partly due to the fact that I spend a lot of time with Suns back in the day. Even so, in the last month I've brought back to life two Octanes, a R4K Indigo, and an Indy, and each had their hardware or IRIX struggles. That said, it's been kind of a fun challenge.

I have left an R3K Indigo that sometimes posts. If it does, it quickly crashes with a "CPU Parity" error. In most cases, it immediately fails POST with a "Replace CPU board" message. The bonus problem with this is that I have an Indigo Elan graphics board, but the machine wont boot at all with that in. Any progress I've made has been using the base LG1 graphics board. Once I get the machine to reliably boot, then I can worry about the ELAN...

After more research, I was incorrect in my error assessment. The error is more of a generic interrupt error. I haven't copied the full stack trace I get, but if it fails the POST test immediately, it shows as "Interrupt Controller Diagnostic" fail.

I'm going to try and confirm if it's a heat related issue (like I had on the previous R4K Indigo) since it seems to start occurring when the the machine warms up a bit. I'll dig up some stick-on heatsinks for an initial trial, or else try and rig up a concentrated flow of air via fan.
 

jdmcs

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I'd swap CPU module from the one board to the other at this point...
The new CPU works in my original system board.
I believe the system board seller failed to adequately protect the compression connectors, and one/both were damaged in shipping. They were, after all, protected by pieces of paper. 🤦‍♂️
 

ScutBoy

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The new CPU works in my original system board.
I believe the system board seller failed to adequately protect the compression connectors, and one/both were damaged in shipping. They were, after all, protected by pieces of paper. 🤦‍♂️
Glad it was that "easy"!