Thunder II GX 1360 - Needs minor repair

[jeremywork]

I got extremely lucky this week and found a SuperMac Thunder II card, listed Buy-it-now on eBay for $30, sold tested to top it off.

https://www.ebay.com/itm/SuperMac-Thunder-II-GX-1360-NuBus-Graphics-Card/283800247264

Unfortunately the packaging was minimal, and it lost a couple components from the back side (well, it appears one wasn't there in the listing photos either, so may not be necessary to run.)

The one labeled L2 wasn't there to begin with, and the one labeled L8 is still physically soldered, but the housing completely shattered and isn't covering it anymore. What does the 'L' in the silkscreen designate? The housing appears to be ferrite or similar and the other components designated 'L' don't carry any alphanumeric markings.

Hoping someone can help me source a pair of the correct replacements, unless consensus is that it's not a problem to run it as-is.

Also, I hadn't encountered it in my reading, but there appear to be different versions of SuperMac's DSP daughtercard. This one is probably an earlier upgrade board, branded 'Image Processing Accelerator' in italic script, and it looks to run at 64MHz. I think the ones that shipped with GX cards were just branded 'GX' in bold, and ran newer revisions of the DSP16A at 80MHz each.

Even with a couple things to fix, I can't complain for that price. Images below:

 

[Unknown_K]

(L) Inductor, same as the part next to it L3

 

[jeremywork]

Thanks! Do you know what that particular form factor is called? It doesn't seem to come up searching for 'smd inductor.'

 

[Unknown_K]

Not a clue. Measure the L3 part and then google the dimensions in mm and see what comes up. You will also need to figure out the value.

 

[jeremywork]

I haven't found any good leads yet. They're 8mm long and 3mm wide... hopefully when I next see my reworking specialist he'll recognize them.

Meanwhile, I picked up a Thunder/24 card (which is a more 'correct' match for my older Image Processing Accelerator daughtercard.) All of its components arrived firmly on-board, thankfully  

It works great in one of my 950s- the DSPs are picked up by the Image Processing Manager 1.1, and SuperVideo 3.1 works great in Mac OS 8.1.

I've heard the GWORLD SIMMs are unobtanium, but I took a stab in the dark and bought a set of these since they were cheap:

https://www.ebay.com/itm/4x-EDI8F3265C15MNC-2Mbit-64K-x-32-64-PIN-SIMM-CMOS-TTL-COMPATIBLE-SRAM-MODULES/112642174763

I suspect they're incorrect, but compared to my experience with the GWORLD SIMMs on the 8•24 GC, 

•The computer still powers on with them installed

•No death chime

•Video output is mostly normal, but with a faint artifacting pattern.

I'm not sure where I can see a readout of how much memory the Thunder/24 recognizes, so I can't tell if they're addressable. I suspect since they do influence video signal, the card recognizes it has a GWORLD cache, and is trying to utilize it, but perhaps these aren't fast enough to keep up? The symptom seems roughly the same whether all four slots are populated, or just the top two.



I noticed one of these packages is -20 instead of -15. The other SIMMs do not have this discrepancy, but the card still exhibits symptoms with only the other two modules installed. I have not removed the stickers to check the speed of the four covered packages.

 

[Trash80toHP_Mini]

Very nice conquest! Gotta love it at that price. Best of luck getting it into tip-top shape. The only reason I have a Thunder IV GX 1600 is that it was listed as something far more pedestrian. [}]

 

[jeremywork]

I love the mis-lists  I found my Keyspan SX-Pro serial card listed, SXPR0 PowerMac 9600 GPU Video Card. Caught in the wrong ebay filter, but a welcome sight nonetheless.

 

[Unknown_K]

Is C92 shattered on the back of the 1600 or is it just my eyes?

I snagged my GWorld RAM from some AVID Targa 2000 Nubus cards and from what I remember you needed to put a SIMM in every other slot for them to work (top empty middle empty and I think they were 2MB each or 4MB?). 

 

[Trash80toHP_Mini]

Does GWorld RAM do anything useful? If so, under what OS?

 

[Unknown_K]

Gworld is more for Apps then the OS. I think Photoshop 2.5 uses it kind of like a VRAM cache so that panning around huge images is much smoother.

Q: What are the four open SIMM slots on my Thunder card used for? Can I add VRAM to them?

A: The four open SIMM slots on the Thunder/24, Thunder/8, and Thunder II Light are for GWorld SIMMs only, not regular RAM SIMMs. GWorld refers to a type of video memory that is used to store off-screen bitmap information for near-instantaneous retrieval by the computer. Since applications have to be specifically written to support GWorld memory, few customers benefit from adding GWorld SIMMs.

Q: Which applications take advantage of GWorld RAM on a Thunder/24 or Thunder/8 graphics card?

A: The Aldus Fetch application represents one of the best examples of an application which takes advantage of GWorld RAM installed on a graphics card. Other applications include the System 7.x Finder, Aldus PageMaker 4.0g (or higher), Adobe Premiere, and PixelPaint Professional.

 

[Trash80toHP_Mini]

I vaguely recalled it was for something like that, was wondering OS timeline given the 1992 copyright on the DSP card. I've got STORM's standalone DSP card that later became the Radius PhotoBooster. My GX is AWOL ATM, I thought it was in the bottom of the 81/110 where it belongs, but there are a couple of other places to look for it. Curious about its copyright dates all of a sudden. It's way past time for snoozin  .  .  ,

 

[jeremywork]

Is C92 shattered on the back of the 1600 or is it just my eyes?

It is shattered, I noticed it later that day. Oddly, referencing back to the eBay photos it appears it was 'tested' and shipped that way.

Thankfully these are marked clearly- if it's the same as the ones surrounding, it'll be 10µ 16v.

from what I remember you needed to put a SIMM in every other slot for them to work (top empty middle empty and I think they were 2MB each or 4MB?). 

I just tested in this slot configuration, but I still get the artifacts on screen. Have you found any program that can read how much memory is installed on the Thunder/24?

I'll see if I can dig up any specs on Targa 2000 SIMM compatibility...