Identifying and confirming fake 68040 CPUs (especially the L88M mask)

JDW

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If I connect it to my LC575, is there some way to get verification via the OS or software?
Install Norton Utilities 3.5.3, then boot into System 7.1 or 7.5.5. Find "System Info" in the Norton app collection and run it. It's a Benchmark utility. It will tell you if the CPU has an FPU or not. Running the benchmark will tell you the performance, which should fall in line with other 040 Macs of the same clock speed. If it doesn't, then you know something is awry.

But even if it has an FPU and works, you need to feel how hot it gets over time, as that will tell you how old it is. The oldest 040 CPUs get the hottest. Even so, at 33MHz or under, it probably could be run even without a heatsink. And I doubt temperatures would be much above 58°C.
 

badferday

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Install Norton Utilities 3.5.3, then boot into System 7.1 or 7.5.5. Find "System Info" in the Norton app collection and run it. It's a Benchmark utility. It will tell you if the CPU has an FPU or not. Running the benchmark will tell you the performance, which should fall in line with other 040 Macs of the same clock speed. If it doesn't, then you know something is awry.

But even if it has an FPU and works, you need to feel how hot it gets over time, as that will tell you how old it is. The oldest 040 CPUs get the hottest. Even so, at 33MHz or under, it probably could be run even without a heatsink. And I doubt temperatures would be much above 58°C.
Thanks. That was super informative. When you say over time, you mean over several times running the computer or during a long time on?
 
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JDW

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When you say over time, you mean over several times running the computer or during a long time on?
Run the machine for 1 hour and give it the touch test, or use a good Thermal Camera if you have one. I personally can't keep my finger on a CPU that is 60°C or hotter.
 

JDW

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It's important to bear in mind the "V" at the end of the part number means 3.3V operation. Consider this 40MHz rated PGA 68040 and its horrifically shocking price...


Want to drop that "V" at the end and get a 5V version? Prepare your hearts for this even more outrageous price...

 

Melkhior

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It's important to bear in mind the "V" at the end of the part number means 3.3V operation. Consider this 40MHz rated PGA 68040 and its horrifically shocking price...
Want to drop that "V" at the end and get a 5V version? Prepare your hearts for this even more outrageous price...
Yes at those price, eBay gambling looks a lot more attractive... For the V version, in a previous post I wondered whether they were also faked. I don't remember the PGA version (with 3 extra pins) in any vintage system (the QFP version, FE, was used in low-power, FPU-less devices like some laptops), does anybody?
 

Kai Robinson

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I wonder if someone (*cough* @alxlab *cough*) would try and make a similar "socket blaster" to use the low voltage 040's in regular machines, as has been done for 486 machines
 

Patrick

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Want to drop that "V" at the end and get a 5V version? Prepare your hearts for this even more outrageous price...
also weird that this version claims to be RISC ?
i thought 68k was ... NOT-RISC.

.. its a nit i admit. .. just something i noticed...
 

badferday

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Ebay seller ericwoosrarechips has some K63Hs in stock. I just bought a couple.

I'm not even gonna bother testing the chip I got from Florida Man. The chance it's an MC/RC40 is basically zero. Back it goes. We'll see about "Returns not accepted".