80386 steppings?

[spongiforme]

Does anyone has information about the different steppings of the 80386?

Looking at various collections, it looks like the datecode of this CPU predates the introduction of the "double sigma" CPUs by a few weeks, but I'm not sure whether it's an engineering sample or not:

[FDIV]

The text on the ES looks crooked to me. This might just be the photo, but if I were you I would examine it under magnification to make sure that peice of text does not differ from the rest of the laser etched text. This is expecially true if it came off e-bay as modern ES fakes made up to take advantage of collectors, although not common, do crop up occasionally. As to predating ZZ release. I have one ZZ that predates this chip (87 week 21). I belive the ZZ release date was week 2, 1987. All that being said ES chips are not always marked in that same way that production chips are. I think this one looks suspect though.

[JAC]

I agree... get that chip under a microscope.

[spongiforme]

The first picture was taken with a scanner using some level of dirt-removal and image sharpening logic.

Here's a different one, taken with a camera using a flash.


As well as scanned at 1200 dpi, with dirt removal and unsharp mask off:

[Cpuswe]

Thats a really nice chip and looks real to me.

Can i add it to the 386-16 category in the library? (It will be added in your name and you will still have copyright to the pic.)

http://www.cpuphotolibrary.com/cat289.htm

[JAC]

Looks good!

[spongiforme]

[spongiforme]

Yann pointed out that the lack of i in the copyright line is... unusual, as well as the significantly mismatched datecodes in the front and back of the chip. If not a fake (and I still want to believe) it's a really weird 386.

[JAC]

There is an extra few weeks between the front and back codes that I would normally expect to see, but I dont think it is unsual.

Long number on back.. 1987 week 3
Shot number on back.. 1987 week 8
date on front ... 1987 week 25


the lack of i is a good observation.. but I note that " i " moves sometimes.

http://www.cpustack.net/intel386/intel386-s40344_nozz_sml.jpg

http://www.cpustack.net/intel386/intel386-l8400785_sml.jpg


One last thing to do is to check the thickness of the ceramic. Compare it with other 386.

That thickness check aside, visually that 386 looks genuine.

[spongiforme]

[jd]

NOPE !!! This is a fake CPU !!!


Doesn't take much to notice it either, the mess left behind is obvious...does anyone see it yet?.......


LET"S PLAY A GAME............I spy with my little eye.........


I'll give u a clue..........


The "style" of lettering on one particular letter, is completely off from any other Intel chips out there.....Just one letter.......





I'll give the answer in a little bit...

[JAC]

the only thing I notice here is the different font on the 3 used on the bottom marking to my chip above made shortly before that es.

(the colour is off due to my scanner settings I used that day )


I dont think it is fake. Looks 100% to me.

[jd]

lol............I think yours is fake too Jac !
I see the same mistake in yours......

But it's not the 3...


I see something far more important then that !

Keep looking....

[FDIV]

Looks genuine. I wouldn't worry to much about the differing date codes either. Many of my 386's from around this time are that way. One dosen't even have a date code on the back. I'm not sure if it got rubbed off or something but there isn't a trace of it.

[jd]

answer............all the circled "m" !!! none of the cpu's that I have seen has a made-up "m" like these ones....the only ones I know are found to be fakes !




JD