Is this a fake 486?

[JAC]

Is this chip fake? :




- The polished back, common with fakes. I have seen it on pentiums and 486's

- All chips I have with 1989 date only have INTEL before the date code.

- Also the spacing/font is different.

- The bottom cap matches chips from a later date, about 1yr+

here is example...

[Borris70]

i don't think so.

i have the same chip:

http://www.cpu-sammlung.de/A80486DX-ES.html

The number of the backside differs in one count

yours: 50391288CC
mine: 50391288CB

Why should a faker do this

[docata-china]

Very good ES! ! Like.
Good landlord fortunate

[JAC]

That chip in the top is my chip, and I think yours came from the same source.. there is the only one seller I know who has these SXE61 chips... so I have no interest in thinking this is fake.. I stand to loose out

Are there any other 486's out there with SXE? specs?

I dont think they were faked for collectors.. take a look at these..



the back has been polished.. these are fake. I will scan one later on the back.

numbers changing on the back does not mean much.. look at fakes like this.. here they just changed the top one.. they probably did not realise the significance of the Q spec at the time..

[spongiforme]

Here is mine:





It's indeed the only 486 I have that uses this lettering. I have a 486SX-16 that has a very similar marker "triangle" at the same spot. When comparing the two, I noticed that the 486DX has a smaller metal cap.

[JAC]

Interesting.. your bottom cap is not polished like mine.
I am not sure what that triangle means, I have seen it on a few chips... does anyone know?

[spongiforme]

Actually It seems that old 486s (from 1990) use the same logo and mask work symbol. See http://www.deuttai.com/?go=show&m=4&f=7

[JAC]

[chip68]

A lowercase "m" may not be legally enforceable, much like a copyright symbol written this way: (c)

Of course, the die itself - and consequently the mask artwork - will likely contain a proper mask work symbol. I put it on every IC I design:



There's no requirement that it be printed on the package.

- CMW

[spongiforme]

There's a whole discussion on copyright protection here:
http://www.edwardsamuels.com/illustratedstory/isc4.htm

This page states:

Curiously, the Semiconductor Chip Protection Act has turned out not to be all that important. Registrations for mask works were below expectations, and in the first ten years after its passage, there was only one reported case brought under the act.

It's well worth a look, at least for the pictures.

[CPUShack]

Theres no requirement that it be on the die either

But if used it SHOULD be in upper case.

By the way, the 486 looks ok to me as far as dates back to front.

[chip68]

[chip68]

[CPUShack]

That is a good nipick to have
Their Z80 label was 3880, and they also second sourced Moto 68000

[FDIV]

I also have one of these SXE61 ES chips. As you have noted one seller has been the supplier on these. I personaly belive they look too good to be faked. All the text is perfect on all of them and the numbers that should differ from chip to chip do. Mine is not polished on the back and does have the triangle stamp. I am quite happy with it. It is in perfect shape and has the old 486 logo which I like. I also like that no speed is marked on it. Anyhow, here it is.