Can anyone identify this 486?

[antimattr]

a few years back I got a small collection of a few CPUs from someone. This chip was in the set and I am trying to learn more about it.

Here are a few observations:

- The CPU came with a note saying it was a 486/66.

- The heatsink is the same style as the type that appears on Intel Overdrive chips. It's epoxied to the ceramic, aligned precisely, and looks to be factory installed.

- The spires on the heatsink are taller than other 486/66 Overdrive chips I've seen. It's similar, but still different than the i486DX4 heatsinks too.

- The plate on the top of the heatsink, where the chip identification information normally sits, is totally blank.

- The very top of the Intel logo is visible under the attached heatsink. It looks as if the ceramic was marked at the factory, then covered.

- The bottom of the chip is marked more consistently with a standard 486DX2/66, not like an Overdrive. At least, from what I can compare based on my collection and the pictures I've found of other i486s.

Thanks!

[debs3759]

Can you test it with Windows 95 and a legacy version of CPU-Z? If the CPUID value is 0433h, it's a B1 stepping 486DX2-66. If 0435h, it's either an aB0 or aC0 DX2-66, or a DX2ODPR66. Not sure how to tell the difference beyond that without removing the heatsink, which may destroy the value for collecting. Someone may be able to narrow it down using the codes on the bottom.

[frag_]

Popular oem heatsink, usually speed grade was on piece of paper glued on the side or on the top like this:
http://www.chipdb.org/img-intel-a80486dx2-66-sl-oem-2925.htm

[antimattr]

[crusty_dog]

with the particular package features (around the cap) seen on the bottom of this and the date of production it is most likely a SX807 A80486DX2-66 (most in this package have a A4 plant code, but there are examples from the Malay plant)

SZ904 DX2ODPR66 also used same bottom package, but no white printing (seen in your picture) was used on the top, as markings were engraved in 486 ODs apart from early production non heatsink varieties.

[antimattr]

Thank you!