Wanted processors and co-processors
I'm looking for rare chips (processors, co-processors) listed in the
table below. In addition to them I'm looking for different kinds of processor
samples: engineering samples, customer samples, mechanical samples, thermal
samples and marketing samples (see the table below for more information).
If you happened to have one or more processors or co-processors from my
wanted list please contact
me. If you have any other chips (not from the list below) and you'd
like to find out how much they are worth please see CPU price notes
on the bottom, or post in the forum.
If you have any datasheets in electronic format, or if you have data
books for you no longer need them please check my list of wanted
|Wanted: Rare microprocessors, co-processors and microcontrollers|
||Manufacturer and part number
||Intel MCS-4 set|
National Semiconductor INS4004D in white ceramic package
National Semiconductor INS4004N (plastic package)
Intel C4040 ES
Intel D4040 without copyright line
Intel MCS-40 set
||MOS Technology 6502 or MCS6502 in white ceramic package
Intel 8008 or 8008-1 in plastic package
Microsystems International MF8008 (without suffix 'R')
||Intel 8080 (part number without prefix)|
Intel C8080C ES
Microsystems International 8080
||AMD 8087 (if it exists)|
|IDT Winchip 3
||Black top K6 processors - any speed
AMD K6-3D 250
Nx586 motherboard with Nx587 socket
||Nx686 any speed (with motherboard if possible)
||Pentium 50 MHz (probably A80501-50)
|Rise Technology MP6 II
||Any speed, in original box
|Wanted: Microprocessor, co-processor and microcontroller
||Usually marked "engineering sample", "eng sample",
"eng eval", "es", or "sample" on the
chip top, and sometimes on the chip bottom. Some Intel 80486 and Intel
Pentium processors are marked with "ES" on the bottom -
these are not samples unless there is an "ES" marking on
the top of the processor.
||Marked "mech sample" or "mechanical sample".
||Older Intel processors were stamped with "CS" on the top
of the chip. The "CS" letters usually differ from other
markings on the chip - they may have slightly different color and
||Usually marked as "Thermal sample"
||The processors that look similar to pictures in press releases and
official product announcements. These usually have a nice looking
company logo and/or product (family) name. Marketing samples don't
have any specific information about the chip - speed, voltage, etc.
me if you have chips from the list above, or if have samples
of any old microprocessors, microcontrollers or co-processors.
|Prices of collectable CPUs, microcontrollers and other chips.
The price of the chip depends primarily on chip rarity, collectibility
Chip rarity is based on how many chips of the same manufacturer
with the same part number and in the same package are available
on the market to collectors. Chip rarity is usually related to chip
age - older chips are more rare, but there are exceptions to this.
Other factors affecting the rarity:
- Package - plastic packages are common, ceramic packages are
more rare, purple/grey side-brazed ceramic DIP packages are even
more rare, and white ceramic packages are the rarest. There are
exceptions to this - for example, purple ceramic Intel C8087 is
more common then Intel D8087. Another example - C8008 in plastic
package is much more rare than C8008 in ceramic package.
- Variations in chip markings - old / newer company logo, font
size, location of the markings, unusual markings or family logo,
and so on.
- Variations in chip package - tin or gold pins, type of the lid,
square or rounded lid, additional marks on the package (for example,
"5" on white ceramic C4004), etc.
- Sample chips - engineering, customer and other samples are valued
much more than production parts. The samples are usually valued
a few times higher than production chips, and in some cases 10-20
times higher. Please see "Wanted: Microprocessor, co-processor
and microcontroller samples" section above for information on
how to identify engineering, qualification, mechanical and other
samples. Please note that modern (Pentium D, Core 2 Duo, Phenom
and others) engineering samples have much higher market value
than their collectible value - if you have one of these processors
you'd be better selling them to people who actually use them than
to CPU collectors.
Collectibility - how desirable this chip to CPU / chip collectors,
or, basically, how big is the chip collector market for this specific
chip. The biggest market is for microprocessors. The market is slightly
smaller for Floating Point Units (FPU), and even smaller for bit-slice
processors, microcontrollers, and first RAM / ROM and support chips.
There is almost no market of old support chips, and very small market
for modern processors - they are not considered collectible yet.
From manufacturers collectors usually favor Intel.
Condition - New / used, quality of chip markings, the presence
of scratches / chips on chip surface, condition of pins, working
status, etc. New chips in working and visually like new condition
are most desirable to CPU collectors. Used socketed chips have lower
price then new chips, and used soldered chips have much lower price
(about 50% price of the new chips or lower). Damaged chip markings
and scratches, marks, and especially surface chips may lower the
price even further. Non-working chips are usually worth much less
than working chips. For boxed processors or FPUs the price is also
determined by whether the box is in original shrink wrap or not,
and the condition of the box. Unopened still in shrink wrap box
in like-new condition is worth more than opened box, and much more
than badly damaged box (even if it was not opened).
Supply and demand for different chip types always fluctuate, which
results in constantly changing chip prices. For example, in the
recent few years we've seen many non-common processors and floating
point units sold by collectors and sellers from Asia, where those
chips are recycled, which reduced the price of many 8086 - Pentium
class processors. At the same time due to limited supply the prices
of some 4004 and 4040 processors went up. Because of the constantly
changing supply and demand for chips and huge number of different
chips variations, publishing up-to-date chip prices is not physically