Mac plus, with a surprise:)

[imactheknife]

The iifx may be more far gone, will see, but this mac plus original had a bonus in it maybe bolle will want to reverse engineer this if he hasn’t already

 

[zigzagjoe]

Nice! I really wonder why Dove liked pulling the plastic case off those 68030s...

 

[Phipli]

Nice! I really wonder why Dove liked pulling the plastic case off those 68030s...

They never put them on. It is cost saving. Chip on board is cheaper than other methods of encapsulation.

I'm just surprised that Motorola sold them dies, or chips in that state.

 

[zigzagjoe]

They never put them on. It is cost saving. Chip on board is cheaper than other methods of encapsulation.

I'm just surprised that Motorola sold them dies, or chips in that state.

Right, best I can tell those are the RP (Plastic PGA) variant of 68030 less the cover. I too am surprised that motorola would furnish them in that state, I'd think the sales quantity is low enough to make it not worth their while....

 

[Phipli]

Right, best I can tell those are the RP (Plastic PGA) variant of 68030 less the cover. I too am surprised that motorola would furnish them in that state, I'd think the sales quantity is low enough to make it not worth their while....

If I remember, Dove was extremely early in the 030 market. I think they were the first to sell an 030 upgrade. They released it possibly at a similar time to the Mac II! But... I'd need to go back and read that edition of Byte magazine in case I'm just muddled.

That could be the reason, perhaps they got an unusual agreement because the norms hadn't been established?

 

[Phipli]

January 1988 advert, a couple of months before the IIx started shipping :


Interestingly the photo shows a gold top.

From Macworld Jan 1988

 

[imactheknife]

January 1988 advert, a couple of months before the IIx started shipping :

View attachment 67746
Interestingly the photo shows a gold top.

From Macworld Jan 1988

Computer boots, will have to see what it says when i get into it. Have the driver floppy so will set it up. Didnt even know these existed.

 

[imactheknife]

Computer boots, will have to see what it says when i get into it. Have the driver floppy so will set it up. Didnt even know these existed.

 

[rplacd]

I actually would love to see this reverse engineered – I know that most of the Macintosh Plus' "secret sauce" logic is in PALs and a few I/O specific chips that at least have well-documented behavior (VIA, SCSI, IWM, SCSI)... the odds of having having a reverse-engineered Macintosh Plus with a 68030 upgrade aren't entirely fully hopeless.

 

[Phipli]

Have the driver floppy so will set it up.

If you have an original version, please image it and back it up

 

[Phipli]

Some tips for photographing a CRT - if you turn down the brightness on the CRT and photograph it with your phone in landscape (you can crop it to portrait afterwards if needed) the screen shows a lot less flicker.

 

[imactheknife]

So this Mac plus logic board obviously works fine. The analog /crt not so much. It powers on, chimes but display stays black. I would imagine the flyback?? or should I try and recap and see what happens? Board looks clean, cut looks good to, no burn in etc.

 

[Kouzui]

Does the screen get all staticky? How does the 4 pin to the CRT look?

 

[Phipli]

The most common fault with Mac Plusses is dry/cracked solder joints on the analogue board, usually the flyback or the cable connectors.

Make sure you leave the machine for a few hours unplugged (a day or more preferably), discharge the tube and don't electrocute yourself. CRT circuits are very spicy.

 

[cheesestraws]

Does whacking it on the AB side help? I'd echo what @Phipli says here:

The most common fault with Mac Plusses is dry/cracked solder joints on the analogue board, usually the flyback or the cable connectors.

Among my Pluses, the big connector between AB <-> LB has been the problem most often.

 

[LaPorta]

What a great find. It appears that it really gives a nice performance boost vs the baseline Plus.

 

[Phipli]

I'm not very familiar with that benchmark, can anyone explain why the time matches the II, but the Dhrystone score is closer to a stock Mac Plus?



Is it doing two tests? If so, what is the one that it is timing? Or has the test been run for a different number of times total? The latter meaning that only the dhrystones / second matter and we're seeing a 24% speed bump from 912 to 1133?

@imactheknife @Snial @cheesestraws @Crutch

I realise the "Sieve" is a prime number Sieve, but am surprised if this is two benchmarks that the Sieve performance increase is 474%, while dhrystones is only 24%.

 

[cheesestraws]

I assume 'sieve' is the Sieve of Erastosthenes. Dhrystone is an integer/string benchmark, but isn't the Sieve of Erastosthenes. My wild guess for the difference would be something to do with memory bandwidth, as I think Dhrystone does a lot of string copying/movement/manipulation whereas the Sieve of Erastosthenes is purely numerical. But that is just a wild guess.

 

[Phipli]

I assume 'sieve' is the Sieve of Erastosthenes. Dhrystone is an integer/string benchmark, but isn't the Sieve of Erastosthenes. My wild guess for the difference would be something to do with memory bandwidth, as I think Dhrystone does a lot of string copying/movement/manipulation whereas the Sieve of Erastosthenes is purely numerical. But that is just a wild guess.

Not prime number Sieve?

Sorry, I kept editing my post. I'll stop now.

Edit : I lied, googled Sieve of Erastosthenes and see it is a specific prime number Sieve.

 

[LaPorta]

Totally off topic, one wonders where the word sieve came from, and why it is pronounced as such.