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| Odd Quadra Motherboard | |
| Posted by: hyperneogeo on 2017-05-27 15:37:29 So I looked for the model #820-0380-02 on the motherboard and came up short. Odd thing is this one is a 40mhz 68040, but it looks nothing like the Quadra 840av. Any information would help!    | |
| Posted by: Gorgonops on 2017-05-27 15:53:37 "Wombat" is one of the codenames for the Quadra 800, and that does look like a 650/800 main board. (The same board was used for both.) Model number on the 650 board is "820-0380-A", so... assuming nothing has been fooled with this appears to be just what the sticker implies, an EVT-2/release candidate prototype of a never released 40mhz version of the Wombat architecture. Where did you find it? | |
| Posted by: hyperneogeo on 2017-05-27 16:16:24 Interesting, thanks for the info! It was dropped off at a local computer recycle center. | |
| Posted by: Themk on 2017-05-27 16:17:30 When you say 'local', is this place near where one of Apple's design/engineering facilities would have been? | |
Posted by: hyperneogeo on 2017-05-27 16:21:19When you say 'local', is this place near where one of Apple's design/engineering facilities would have been?Yes, it was near the Cupertino Apple HQ | |
| Posted by: Themk on 2017-05-27 16:27:23 Well cool! Nice find. Now all you need is a computer to stuff it in. I wonder if the ROMs might be a different revision then the final release ones? | |
| Posted by: unity on 2017-05-27 18:05:01 Many of the early boards say Wombat - but yes this is a PVT (production verification test) making it the last version of a prototype. In fact, it may be no different than the production. The purpose of PVT is to make sure the product can be produced at full speed with no issue. So a design change from PVT to production can happen, but often does not. Its a nifty board! | |
| Posted by: Gorgonops on 2017-05-27 19:16:39 Wonder why they canned a 40mhz production version; that extra 8mhz in an A/UX compatible board would have been a nice swan song for the "business" Quadra. | |
| Posted by: unity on 2017-05-27 19:37:30 I dunno. My and another user talked about Wombat boards a while back. The board was used in two Macs. Very few have ROM slots like this one. I have an -04 that was in a Centris case and is 32mhz with ROM SIMM. We looked over machines and such and we just got more confused as to what Apple was thinking/building at that time. My guess was it would have competed with a higher end model. | |
| Posted by: hyperneogeo on 2017-05-27 19:44:45 I honestly thought nothing of it when I picked them up. I saw a bunch in a pile, saw they had 68040 processors on it and was like "Could always use those!" Weird... | |
| Posted by: Themk on 2017-05-27 20:12:49 I wish I could go there and pick some up!!!!!! Nice find! I don't exactly have a 650/800 case, but, I have enought parts to cough together a working system if I had the board. May I ask, how much per piece were they? | |
| Posted by: hyperneogeo on 2017-05-27 20:14:43 I picked them up in a big lot with a lot of other things, so it's hard to say. | |
| Posted by: Themk on 2017-05-27 20:21:03 Well cool! Enjoy them! | |
| Posted by: Cory5412 on 2017-05-30 13:14:15 This board got discussed in #68kMLA on Oshaberi the other night. I wasn't there, but I saw it in the backlog. A 40MHz version of the 650/800 would have been great, and for the slight increase in RAM capacity (136>128) that comes from the onboard RAM and for the A/UX compatibility that Gorgonops mentions, this would have been a really great system. Today, or even in ~2001 when I got my first 840, I would likely have gone for a 40MHz version of the 800 instead, mainly because I don't really "need" the A/V functionality, and the A/UX functionality would have been intriguing. Someone mentioned that it looked like a Quadra 700 board, which it does, if only because physically, the IIcx, IIci, Quadra 700, C/Q650 and 800, and PM7100, as well as the IIvi and IIvx and Performa 600, are all pretty much identical. I don't remember off hand if the 8100 also has the same physical form factor or if the 8100 was structured more like the Quadra 800, whose board has its internal connectors mostly along the top. The Quadra 700 was introduced in 1991 and the 650/800 were introduced in 1993, so it's very possible that the development occurred in a Q700 case. Anyway thank you for posting this! | |
| Posted by: Unknown_K on 2017-05-30 16:49:30 Maybe the PDS slot would not work at 40mhz? | |
| Posted by: hyperneogeo on 2017-06-23 22:33:21 OK, I went ahead and booted it up and it reported it was 33mhz. I looked at the crystal and it was indeed a 16 something crystal..however it looked like someone replaced it with that one. Do you think I should put it back to 20mhz? | |
| Posted by: Macdrone on 2017-06-24 09:56:05 My guess would be maybe it was not stable is why it was down clocked. | |
| Posted by: nglevin on 2017-06-24 15:46:26 It sounds a bit more like a near-production Quadra 800 mobo, if it can't be safely clocked to 40. Mine has a 40 Mhz 68040 in the CPU socket, but I've only been able to get it as far as 38.?? Mhz with a MacClip temporarily overriding the clock crystal. Past that point it becomes very unstable. | |
| Posted by: Bunsen on 2017-06-28 07:06:06 Try a heatsink or two? CPU and whatever else feels warm. | |
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