Q: Tyan S1830S & PIII 1GHz

[John Turco]

Hello,

On my Tyan S1830S "Tsunami" (a venerable AT mainboard, with AMI BIOS
V2.00.02), I recently replaced an Intel Pentium III 600E processor (Slot
1) with a PIII 1GHz (FCPGA Socket 370, product number RB80526PY001256).

Each of these "Coppermine" chips is of the 100MHz FSB variety, which is
the fastest the S1830S's 440BX chipset officially supports. (I also
needed an adapter, so I bought an inexpensive "Super Slocket III," off
eBay <http://www.ebay.com>.)

Anyway, everything seemed to go smoothly, except for the fact that the
new CPU only runs at 900MHz! The BIOS and various utilities [including
the latest version (7.1) of Intel's own "Processor Frequency ID"] all
agree on this issue, too.

The RB80526PY001256 is using a 9x multiplier (i.e., 9 x 100MHz =
900MHz), instead of the proper 10x, apparently. I've tried different
BIOS settings, such as temporarily increasing the FSB to 112MHz, which
results in approximately 1GHz (9 x 112MHz). Alas, that causes system
instability (e.g., AVI files always crash).

As all PIII's are "multiplier locked," how can I >safely< get the full
1GHz out of my purchase?

Incidentally, according to an Intel Web page, the RB80526PY001256 is
"for existing embedded applications using the Intel® 440BX chipset
only." Could this have anything to do with my current problem?

Please, reply to the newsgroup, exclusively; thank you, in advance, for
any helpful information.


Cordially,
John Turco <[email protected]>

 

[John Turco]

Hello,

On my Tyan S1830S "Tsunami" (a venerable AT mainboard, with AMI BIOS
V2.00.02), I recently replaced an Intel Pentium III 600E processor (Slot
1) with a PIII 1GHz (FCPGA Socket 370, product number RB80526PY001256).

Each of these "Coppermine" chips is of the 100MHz FSB variety, which is
the fastest the S1830S's 440BX chipset officially supports. (I also
needed an adapter, so I bought an inexpensive "Super Slocket III," off
eBay <http://www.ebay.com>.)

Anyway, everything seemed to go smoothly, except for the fact that the
new CPU only runs at 900MHz! The BIOS and various utilities [including
the latest version (7.1) of Intel's own "Processor Frequency ID"] all
agree on this issue, too.

The RB80526PY001256 is using a 9x multiplier (i.e., 9 x 100MHz =
900MHz), instead of the proper 10x, apparently. I've tried different
BIOS settings, such as temporarily increasing the FSB to 112MHz, which
results in approximately 1GHz (9 x 112MHz). Alas, that causes system
instability (e.g., AVI files always crash).

As all PIII's are "multiplier locked," how can I >safely< get the full
1GHz out of my purchase?

Incidentally, according to an Intel Web page, the RB80526PY001256 is
"for existing embedded applications using the Intel® 440BX chipset
only." Could this have anything to do with my current problem?

Please, reply to the newsgroup, exclusively; thank you, in advance, for
any helpful information.

Cordially,
John Turco <[email protected]>

Hello,

I originally posted the article, above, on 11-21-04...and yet, only
stumbled upon the solution, within the past week or so.

You see, my particular SL5QV/RB80526PY001256 processor happens to be a
rare engineering/evaluation sample, boasting an unlocked multiplier.
Instead of ignoring the mainboard's manual multiplier settings, as all
of Intel's modern production (i.e., multiplier locked) CPU's do, it
obeys them!

Hence, on my primary PC (which had been limited to 900MHz, with the
SL5QV installed), the relevant jumper configuration was:

JP8 - ON
JP9 - OFF
JP10 - OFF
JP11 - ON

However, a secondary computer (with an identical S1830S board) ran the
SL5QV at full tilt, and even a little beyond (1050MHz). Its settings
were:

JP8 - ON
JP9 - ON
JP10 - ON
JP11 - OFF

The Tsunami's 1999 users booklet (written before the Pentium III's
release) states that those multiplier settings are x3 and x4,
respectively; whereas, the SL5QV interpreted them as x9 and x10.5,
obviously.

Surprisingly, with all the jumpers open, it bottomed out at a mere
400MHz. (Which, therefore, had to be the processor's actual x4
multiplier.)

Trying the '99 book's x4.5 and x5 settings allowed me to reach a seeming
1000MHz, but, WinME refused to load. I concluded that the SL5QV was
running much faster than the POST screen displayed, and Windows simply
couldn't take it.

(All testing was done with the Tsunami's default 100MHz FSB, by the
way.)

I'd already upgraded both boards' BIOSes to the final Beta version
(V2.00.03, extracted from 1830c28.exe), although, I'm not entirely
certain it was absolutely necessary. They can always be flashed back
to the previous V2.00.02, regardless.

Thus, I now possess a slightly speedier CPU (1050MHz vs 1000MHz) than
advertised. I'd ordered it from Star Micro <http://www.starmicro.net>,
on 10-3-04, for a rather reasonable $69 (free UPS Ground Shipping,
included). I was a bit stunned to see that it's still being offered,
nearly a year later:

Star Micro/PIII 1GHz 100MHz FSB 256K FCPGA Socket 370 CPU OEM: $75
http://www.starmicro.net/detail.aspx?ID=94

Further details of my long struggle can be viewed, over at TechIMO
<http://www.techimo.com>:

TechIMO Forums > PC Hardware and Tech > Processors, Memory, and
Overclocking > Tyan S1830S & PIII 1GHz
http://www.techimo.com/forum/showthread.php?t=148678&page=1&pp=20

Happy reading, and good luck, to all the interested S1830S owners out
there!


Cordially,
John Turco <[email protected]>