K7550MTR51B R

[Neon_WA]

Has anyone worked out why some 550 K7 slot Athlons are marked with a R, rather than a A or C

A = Pluto core
C = Argon core
R = ?????

like this one http://www.cpupages.com/store/index.php?id_item=20

most seem to be from mid 2000, so late production for a 550

[Neon]

Neon_WA, I just found one of these. Running it right now, it is CPUID=612 revision C2

So it seems to be Argon core, the same as C

Date code is 0025, in agreement with your observation.

I will put a scan up in the next few days.

[Neon_WA]

[Chook]

Just to confuse the collectors of course!

[CPUShack]

how do the dates on the cartridge match up with those of the components on the PCB?

[Neon]

Since I have only this one, I do not plan to take this one apart.

Do you think R may stand for reworked?

[CPUShack]

[Neon]

Here is un photo de la top edge

[gshv]

There is also a picture of AMD-K7650MTR51B R in the pictures tab here:

http://www.cpu-world.com/CPUs/K7/AMD-Athlon%20650%20-%20AMD-K7650MTR51B%20C.html

I have no idea what "R" can stand for. If the CPUID is the same, then, perhaps, there are changes in the cartridge or PCB design?

Gennadiy

[Neon_WA]

I have 2 sitting at Avicc.
One is to strip down and compare markings on the PCB with a normal 550, but will have to wait till i get them shipped to me.

These are being sold at one place as "Refurbished by the Manufacturer"

Genna if they interest you let me know and I will pass the link to you or you can get it off Neon

this site gives a good method to open slot A cartridges without destroying them
http://www.dansdata.com/thunderbird.htm

[Neon]

R could stand for "reworked", meaning it was a nonworking unit that got returned.

The faulty component was then removed (desoldered) and replaced with a good one, the repaired unit tested, and a cartridge with R label attached.

That is why CPUShack asked if some of the surface mount components have different dates from the cartridge

[gshv]

[Neon]

gshv, yes it is Compuvest.

My curiosity exceeded my caution. As this was my first attempt to remove PCB from cartridge, there was some damage to the cartridge, and only a few light scratches to PCB.

The date codes:
Cartridge: K7550MTR51B R 230025507634
CPU: K7600CURAFC R 9947APMW 91027340100 26650
L2 Cache: NEC D432937GF-A31-H 0011K7019
L2 Cache: NEC D432937GF-A31-H 0016K7005
PCB: PWB1000034-010 0020-4090

None of the CPU or L2 cache components are newer than the PCB date, so there is not obvious evidence of rework.

However, note the CPU is marked as 600 MHz, so perhaps R means remarked?

[CPUShack]

yah likely they took some returns, re tested them at a lower speed and stuck them in a new cartridge (and perhaps a new PCB even)

[debs3759]