Stretching beyond limits.

[AgentX]

Specs
--------
CPU - Intel Celeron 400MHz (128KB Cache) (Installed on a SlotKet)
Motherboard - Unknown (OEM?) Intel i440ZX-ALI513 Chipset (Slot-1)
BIOS - Procomp 03/02/1999-i440ZX-ALI513-2A69KPNDC-00 (B687Z)
RAM - PC133MHz (128MB@2) - 256MB Total
Video - nVIDIA Riva TNT2 M64 32MB

For more info on my motherboard & BIOS, get this PDF from Procomp:-
ftp://ser2.procomp.com.tw/download/b687z.pdf

Background
---------------
As it's obvious, I got this low-spec PC in September of 1999. Since then,
I've been modifying it to suit my needs, for example I replaced 64MB
PC100 RAM and installed two modules of 128MB PC133 SDRAM.
Unfortunately, my un-named motherboard has no more memory banks
left to install more.

Last year, I installed a Seagate 80GB HDD ...which my mobo failed to
detect and caused hang-ups at startup. I had to set the 32GB jumper and
Seagate DDO software to enable all 80GB of space for Windows. Things
were running smooth until ...

I found this forum while searching for some hardware info on Yahoo.com.
I had to go through countless of info-laden posts just to satisfy my thirst
for knowledge. Within minutes, I learned that it was possible to get a
modified firmware for my version of BIOS. Strangely, no updates are
avilable from Procomp site. I downloaded Apple's BP patcher and then
patched my original BIOS firmware successfully. Now my motherboard
happily detects all of the 80GB HDD without any extra 32GB jumper. Cool!

The next BIG step
----------------------
Given the severe limitations imposed by my cramped motherboard, which
has almost no extra features (like hardware monitoring chip, extra BIOS)
to boast of ...the only option left to impove on my computer's performance
is to completely upgrade it with the latest available Intel of AMD solution.

No, it's not! I don't want to throw away my beloved companion for years,
just because it can't take high-speed processors. And, I don't quite feel
like upgrading until and unless the AMD64 platform becomes more afford-
able and more common than it is today. I'm studying for my graduation
degree in Computer Science, and my PC still compiles all my C, Fortran
and assembler codes easily. All I play is "Age of Empires", and my good
old beige box can handle it beautifully, even if it has to order the pesky
TNT2M64 (running at 2x AGP) to fill my 19" 1280x1024 screen.

But ...I sure would like to upgrade to the fastest CPU my mobo can take.
According to the manuals and that PDF, it can only go as far as a P3 550.
However, after scanning the web for the required information, I walked
through a few sites and pages where the description of a Tualatin Celeron
1.4GHz working on a 440BX were given. Though I couldn't exactly got ti
understand the little details about core voltage changings by connecting
the pins etc, I can easily follow all the steps precisely if the situation
warrants so. I'm willing to understand all those tiny details with the help
of which I can make my system run faster than ever.

The help needed
---------------------
I would like to know if my motherboard can take a Tualatin Celeron or
a Williamette Celeron 2.0GHz or more (easily available). My current CPU,
a Celeron 400, sits on my mobo with the help of a PPGA SlotKet. I would
like to know if it's possible to tweak voltage settings to allow modern
processors to run on a 440ZX. And also, what is the latest and fastest CPU
which can be made to share my beige box with my old, very old, mobo.

Regards,
AgentX

[Denniss]

with a patched Bios to support Tualatin type CPu and a special but expensive Slocket (with voltage regulator) a Tualatin should work .

With luck this boards support Coppermine Celeron/P3 with 100MHz FSB but you may set VCore manually to 1.8V if the Board does not go lower (via Slocket)

[AgentX]

Well, I've already patched my BIOS with BP patcher 4.51, so I suppose it
now supports Tualatins. Is it necessary to buy a special slocket with
"voltage regulator", even if I follow the pin connection and modification
articles on the net? And, what if I can't find a Slocket made by reputed
companies, would I still be able to run any 100MHz FSB CPU?

Please shed more light on this subject.

Regards,
AgentX

[Denniss]

The need for Slocket with VRM depends on how much your motherboard is able to deliver and how low in voltage it goes .
Early boards usually go down to 1.8V and not less so any CPU demanding less voltage result in non-boot .
1.4GHz Tualatin might be too much power for the OnBoard VRM on the motherboard .
At best I'll try to get a Coppermine Celeron or P3 ~1GHz with 100MHz FSB

[Ritchie]

I looked at the original post and am thinking on the memory issue, depending on how many rows of memory the board supports, you may be able to squeeze a bit more RAM out of the system by installing a double sided 256MB module, as I understand that the ZX/BX chipset supports these. You might not get 2 * DS 256MB modules recognised, but perhaps the board might allow 1 * DS 256MB + 1 * 128MB.

[Denniss]

Two doublesided 256MB sticks with 16x8 internal organisation and 16 chips each should work without problems but they might be a little expensive .

[AgentX]

According to the mobo manual, only 256MB of RAM (2@128) is supported.
Allow me to add that my poor mobo doesn't have *ANY* voltage setting
jumpers on it. It doesn't even have voltage/clock increment option in BIOS.
The only avilable option to change CPU/PCI clock speed is given in the
chipset features setup menu in BIOS. The option "CPU Host/PCI Clock" offers

124/41MHz
75/37MHz
83/41MHz
66/33MHz
103/34MHz
112/33MHz
133/44MHz
100/33MHz
Default

I can successfully OC my current Celeron 400 to 450 and 500MHz speeds.
However, the system becomes unstable at 500MHz with the stock CPU fan.
Is it safe to assume that my mobo supports clock speeds upto 133MHz,
and it can take P3s or CuMine/Tualatin Celerons upto 1.4GHz or more?

I've read numerous articles about OC'ing Tualatins or running them on BX
boards. I've gathered that having a voltage tweaking option in BIOS or in
form of jumpers is beneficial in overclocking.

On the other hand, I'm having a hard time understanding all those VCore,
VSS, VID and other similar things. Denniss, you say that it's necessary
to manually tweak VCore to 1.80 or less ..but how do I do that if this crap
mobo doesn't support manal voltage adjustment jumpers?

Given all these problems and shortcomings, is it still possible to install a
CuMine P3 or Tualatin Celeron? Kindly try to explain all these things to me
if you've got some time to spare, else recommend any site with all the
needed information for an OC-beginner like me.

BTW, I've read soewhere that even older Socket 370s can be made to
accept Tualatins or CuMines. How can it be possible for a PPGA to accept
an FCPGA/FCPGA2 type CPUs? If it can be done with the pin connection
and isolation hacks, do I need to purchase an FCPGA/FCPGA2 Slotket?

Confusions...

Regards,
AgentX

[Denniss]

The ZX-100 chipset is capable of running 100MHz FSB and goes stable up to 112MHz - all above has PCI-Clock too high (same with 83MHz FSB) .
The i440ZX-100 should have the same Limitation the i440BX so 256MB doublesided with 16 chips and 16x8 is the max

IF your slocket has Voltage jumpers try 2.05V or 2.1V

[Ritchie]

From what I am learning about memory support it is the chipset that dictates the maximum capacity memory chip that is compatible. If the is true, any ZX/BX based board should work with 256MB modules, unless something has been encoded into the BIOS to restrict back to 128MB (or further...!)

I understand that you probably have a concern about forking out money for DS 256MB modules that are rising in price while you are not confident that they will be compatible. Therefore I have two suggestions.

1) If you can borrow 1 or 2 DS 256MB modules and trial them, before you make a purchase decision.

2) You could take a gamble that the DS 256MB modules will work and purchase an identical pair of compatible and reasonably good quality memory. I suggest this because you may find that even if they will not work in this system at the present, you may find them a useful upgrade 'ingredient' at some time in the, perhaps admittedly not foreseeable, future, at a time when others also are after them but are either complaining that they are available and too expensive or that they are no longer available. Remember that these modules are likely to dissappear from new parts sales at some time in the not too distant future and that before they do they are likely to get more expensive - if financially viable for you you could purchase them now when they are still easily available and cheaper than they probably will be. Also if you get modules that offer a lifetime warranty it means that they are replaceable without the issue of whether you can purchase new replacements or not, if needed.


Sorry for the long post but one other point I wanted to add - I read a hardware book that gives an example of a board or system that had documentation stating that the maximum sized memory modules that would work with that board were 16MB modules. However, that board did actually work nicely with 32MB modules, and the reason given for this scenario was that the manufacturer (probably) listed 16MB modules as the maximum size compatible modules because 16MB modules was the highest capacity module available at the time of the board's manufacturer - point simply being that a similar situation may apply to your board.

[AgentX]

Okay, lets cut it short.
I guess it won't be possible to run Celeron 1.4GHz (Tualatin) on my mobo.
So as Denniss suggests, I should opt for CuMine 100MHz FSB CPUs. But,
what I still can't figure out is whether I'll be able to run CuMine ~1GHz on
my mobo without any manual voltage tweakings or not. I also need to
know if I'll have to buy FCPGA 370 Slotket for CuMines or my older PPGA
370 for Celeron 400 will handle them (I guess not!). And, must I go for a
voltage tweak enabled slotket even in case of 100MHz FSB CuMine CPUs?

Your invaluable insights are most welcome!

Regards,
AgentX

[Denniss]

You need a FCPGA capable Slocket .
Many of them have voltage select jumpers - you are able to set the voltage to ~1.2V up to ~2.5V but your mainboard voltage regulator has to support this voltage .

As I said many older boards should support at least 1.8V as minimum Voltage and some even go lower .

[Ritchie]

OK, With your current processor, the Celeron 400, that would be running a 66FSB. With the FSB speeds you listed that your board supports, (I am interpretting the right hand column as PCI bus speed) it looks like 100 FSB is comfortably supported in addition to the 66 FSB, for a PCI bus speed of 33MHz. So you should be fine upgrading to any processor that requires 100 FSB, which I recommend. If you went to a CPU that supported a 133 FSB, you do not have a 133/33 CPU Host/PCI Clock. The PCI bus will be stable at up to 33.3MHz but trying to push it any higher than that introduces instability to the system. You have a 133/44 listed which is too fast - it seems the board doesn't really have proper, stable support for a 133 FSB CPU.

I would personally go for a Pentium series CPU, rather than the Celeron, and aim for about the faster 100 FSB in those that you can obtain. And you mentioned that you are running PC133 RAM in your original specs; just remember that the CPU FSB requirement should be at least matched or bettered by your RAM (and board). So obviously if you stick with your PC133 RAM you will be fine; if not then if you install a 100 FSB CPU then be sure to use at least PC100 RAM. Although you probably are aware of that I know that when you need some RAM and have some spare sitting around it can be easy to overlook this.

[AgentX]

Thanks for all the much needed information!
But, I still have a few questions left ...so I won't be waving goodbyes any
time soon.

1. Can I run P3 (CuMine) 133MHz FSB CPU on my mobo. Is it possible to
run it slower at 100MHz FSB? I'm asking this just because I may not be
able to find 100MHz FSB P3s in my locality. All the P3s are very rare these
days.

2. Can I run my existing Celeron 400 (66MHz FSB) at 600MHz (100MHz)
speed? My PPGA-370 SlotKet has a jumper which allows 66 and 100 FSB
speeds. I hope all other components will run fine as my mobo supports
33MHz PCI speed at 100MHz FSB. I've already tested that jumper on the
slotket and it works ...at least the POST shows the Celeron running at 600
MHz. I didn't allow any further operating of my system at that speed, as
I was afraid it could damage the processor. I've even noticed an article
on TomsHardware which explains how the 66MHz CPUs can be run at 100
MHz speeds by insulating the B21 pin on the Slot-1 interface. So I assume
it should be possible to do that. But how?

Today, I replaced my older 230W SMPS with a new 300W one. Also, three
80mm fans were added to the system case to allow better ventilation. Am
I preparing for an OC-ride ...who knows.

Regards,
AgentX

[Denniss]

133Mhz CPU will run with 100MHz FSB but they are running much slower as their MHz rating comes from FSB x Multiplier .
IF you only find 133MHz P3 try Celerons 800 or higher as they have 100MHz FSB + OC potential
Celli 400 at 600 is nearly impossible without raising VCore to ~2.4V and a lot of luck

[AgentX]

Okay, I'll try to find 100MHz FSB P3s then. BTW, I tried to run my Celeron
at 600MHz today, after installing a new Heatsink-Fan. The POST went okay
but the system didn't even load the NT loader ..it just restarted the system
again after completing the POST. The heatsink became very hot, so I had
to reset the FSB back to 66MHz. Argh!

Well, how can I determine the core voltage range supported by my mobo?
The skimpy manual, which came with it, doesn't say anything about core
voltage at all. Not even the BIOS has options to change or display these
settings. Is there any way I can OC my Celeron 400 to operate at 100MHz
FSB, thus giving a total of 600MHz?

You say that it isn't possible unless the VCore is changed to 2.4V, however
the default VCore for Celeron Mendocino is only 2.0V, isn't it? How safe it
is to increase the VCore to such an extent? Can you point me to some
working links where changing of voltages are described, for the P2s or P2
Celerons? Tualatin mods are all I can find on the net. TomsHardware does
talk about covering some pins on the slot-1 card for increased VCore, but
I'd rather like to have the PPGA-370 mod for that.

Thanks,
AgentX