Is this Timna?

[Neon]

The only part number is T012A287 . The core looks like the same size as Pentium III Coppermine.
Notice that the pattern of radiating traces on the front side is different from Pentium III, so I thought at first maybe this is a nonfunctional "mechanical sample", but then I read about Timna.
http://www.cpu-world.com/CPUs/Timna/index.html

The pin arrangement is different from socket 370. The red arrows point to missing pins; the yellow arrow points to an extra pin. The extra pin prevents insertion of the chip into socket 370.

Most of the other Timnas I saw had part numbers like RB80529RZ###128 and a Q-Spec, but this one has neither.

[gg1978]

That would be a pretty good guess.. I think there was a post on this subject in the past here, though i forget exactly when it was..

[CPUShack]

here is my Timna front and back
Looks like a match

[Neon]

Ah, very nice! It looks like a match, all right.

Was Timna only Celeron, or would there have been Pentium III also?

[CPUShack]

Value segment, so only Celeron

[D.8080]

Someone here has a working board for Timna cpus.
Browse the site as it was interesting.

Nice find!

[Neon]

I found it; it's Windmiller 4 years ago. Thanks.

http://www.cpu-world.com/forum/viewtopic.php?t=11663