Fake CPU's?

[MaxP779]

I dont really understand fake cpus, but ive seen it mentioned a few times that a certain CPU is fake, maybe someone can answer my questions

How do you identify one?

How do you get a fake CPU to begin with? These things need fabs and clean rooms and all that high tech manufacturing stuff right? Or is a fake CPU simply a lump of ceramic and metal dressed up to look like a CPU with no silicon die inside?

Is it that its not actually a fake CPU its just made by someone other than whats is printed on it?

[jrmunro]

I`m no expert but usually it`s a cpu of lower frequency remarked to a higher one or as in Amd chips had bridges changed also.

[CPUShack]

yup, usually they are remarked as a higher spec.

Sometimes its a completely different chip marked to something else.

Other times it is a empty package (no die) marked as something else

[naked1300]

http://www.cpu-galaxy.at/Article/fakes.htm

[Neon_WA]

[Chook]

Ceramic fakes such as 486 and Pentiums were usually made by grinding down the top surface of the chip to remove the old engraved markings and then engraving new markings on them - eg grinding down a 486DX2-50 and then engraving it as a 486DX2-66.
In most cases they are easily noticable as the fakers rarely got the font of the engravngs exactly the same as the original. The grinding is uaually evident too as the chip is slightly thinner than it should be and lacks the chamfered edge. Fakers often had the wrong dates such as the die date being later than the package date (should be the other way around) and sometimes even had the sspec wrong.
Although what I just said makes it seem easy to spot fakes, you usually have to be a cpu collector to pick up the differences. I had some fakes in my collection for ages before they were pointed out to me!

[WFS2005]

I have a SU046 too, lol

[MaxP779]

Ah so its the ceramic ones i need to watch out for.

[CPUShack]

oh they fake plastic ones too lol

[Cpuswe]

I have a category on chipdb.org for fakes. They go for anything, not only ceramics

http://www.chipdb.org/cat------fakes------1.htm

[CPUShack]

and its not just fake CPU's
http://www.autoblog.com/2011/02/16/report-counterfeit-parts-overwhelm-china-include-fake-airbags/

Here the fakers put people lives at risk. Well done idiots.