VOGONS

Search

Common searches

Questions regarding the ASUS P/I-P55T2P4 rev 2.3

Topic actions

First post, by Wilius

Posted on 
User metadata
Rank Member
Rank
Member

Hello everybody,

I've recently got a vintage computer for free.
This neat little machine is perfect for my retro gaming project.
After I took it apart, I've discovered that the motherboard is the legendary ASUS P/I-P55T2P4 revision 2.3.
A while ago, the popular Youtuber Lazy Game Reviews (aka. LGR) uploaded this video: https://www.youtube.com/watch?v=9yT9KPQqBtE, which features the same board.
In my opinion, this is one of the best videos on YouTube, which shows this board in great detail.
This video heavily inspired me to build a similar system.
However, I'm having many questions about my upgrade plans.

Q1
I'm considering upgrading the memory to 512 MB, which means I'll have to install a TAG Ram.
LGR showed a Winbond w24257ak-15 in his video.
I don't have the same model, but I do have Pin-compatible chips, which might work as well.
Here are my options: ISSI IS61C256AH-15N, MOSEL MS62256H-15NC, Motorola MCM6206CP20.
Which of the candidates should I pick?

Q2
I'd like to increase the L2 Cache to 512k, by adding a COASt module.
At the moment, I only own a single COASt Module of unknown size. It's labeled as PT-911A.
Unfortunately, I couldn't find anything about this module on the internet.
The Cache chips are NEC d431232lgf-a8. Unfortunately, I was unable to find any data sheets for these chips.
Is this a 256k module and can I use it on my board? If requested, I'll take pictures of it.

Q3
Of course, the Dallas RTC battery on my board is empty, hence I need to replace it asap.
LGR has replaced his Dallas RTC battery with one of those fancy Drop-in replacement modules, but these things are rare to come across in Germany.
I don't want to modify the existing one, or replace it with yet another DS12B887 RTC battery.
Has anyone an idea where I can get a cheap replacement module?
It would be great if the article directly comes from Germany.
Ideally, I'd love to get my hands on the GW-12887-1 from "The Glitch Works".

Q4
What is the best and most stable BIOS version you recommend for this board, and what flash tools do I need?
I'm currently searching for a newer BIOS, because the HDD I'd like to use is larger than 32 GB.

I'm sorry for the many questions.

Thanks in advance for helping me.

Reply 1 of 8, by Horun

Posted on 
User metadata
Rank l33t++
Rank
l33t++

Being a rev 2.3 it will not support MMX (no 2.8v core support like rev 3.x) see: http://web.archive.org/web/19970607091346/htt … 55t2p4-tech.asp
That page also gives some Cache module info.

What BIOS version do you currently have ? The last one is t25i0207.zip ver. 0207 11/25/1998 with NSTL Hardware Tested Year 2000 Compliant.

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 8, by Wilius

Posted on 
User metadata
Rank Member
Rank
Member

Thanks for the quick reply.
I'm aware that this board does not support dual voltage, hence no MMX.
But this is fine, as the CPU isn't the most important thing for my build.
Pretty much every program, which I'm going to run on this machine, doesn't need MMX anyway, thus I don't need to worry about this.
My Pentium i200 is all I need.
As for the BIOS, it's currently version (Award Modular BIOS) v4.51PG.

Reply 4 of 8, by Chkcpu

Posted on 
User metadata
Rank Member
Rank
Member

On Asus boards, the BIOS revision is shown on the boot screen as #401A0-0207 or #401A0-0207-2.

Revision 0207-2 from 04/28/99 is actually the latest from Asus for this T2P4 board. This 0207-2 BIOS however is still limited to 32GB HDDs.
I used this 0207-2 BIOS to make a patch J.2 version with HDD support up to 128GB. This is exactly the same BIOS as LGR uses in the YouTube video you linked. You can find this BIOS at:
http://www.steunebrink.info/k6plus.htm#patched

For flashing an Asus socket 7 BIOS, I use the proven Aflash v2.02. Newer versions of Aflash don’t support these older socket 7 boards anymore. You can download this flasher from my site at: http://www.steunebrink.info/aflash202.zip
But of course you can also use Uniflash. 😉

Note that if you update from an earlier BIOS revision, like 0205 or 0206, you have to flash with bootblock. Because the 0207 bootblock is different from earlier versions you need to update the BIOS bootblock as well, but remember to set JP8 to Enabled to allow this.

Edit: updated the links to my website.

Last edited by Chkcpu on 2023-07-01, 12:01. Edited 1 time in total.

CPU Identification utility
The Unofficial K6-2+ / K6-III+ page

Reply 5 of 8, by Wilius

Posted on 
User metadata
Rank Member
Rank
Member

Whoops, I didn't know about that, thanks for telling me.
So, if I got this right, then the BIOS revision should be #401A0-0105.
Many thanks for your help, I appreciate that.

One more question. Should I replace the Dallas RTC battery before updating the BIOS?

Reply 6 of 8, by BitWrangler

Posted on 
User metadata
Rank l33t++
Rank
l33t++

I've got one rev 3+ (Had K6-2s running on it in past) and a couple or three plain Janes of earlier revisions... When they see light of day, I know what they're getting... I already turned up some K6-233 3.2/3.3V versions, muhuhahaaaa.... okay, I'll prolly give a home to the poor lost little P200 too. Back in early 2000s, I was trying to brain out a quick and dirty split vcore fix, with 3.3V dropped with a few high amp diodes or something.... did not get very far with that... crap happened, then it was a couple of years later and 450Mhz CPUs didn't seem real useful any more so it all got shelved. (Basically flash got fat really quick, and also got big, so you ended up needing 1.5Ghz just to see most web content)

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 7 of 8, by Wilius

Posted on 
User metadata
Rank Member
Rank
Member

I've got great news.
My COASt module is working.
With that being said, question 2 has been solved.
Before I'm going to flash the BIOS and replace the DS12B887, I would like to set focus on the TAG Ram first.
Is the ISSI IS61C256AH-15N going to work on my board?
What about the MOSEL MS62256H-15NC and Motorola MCM6206CP20?
Could they work too? As far as I know, all of them are pin compatible with each other.

Reply 8 of 8, by Chkcpu

Posted on 
User metadata
Rank Member
Rank
Member
Wilius wrote on 2021-09-11, 21:15:
Whoops, I didn't know about that, thanks for telling me. So, if I got this right, then the BIOS revision should be #401A0-0105. […]
Show full quote

Whoops, I didn't know about that, thanks for telling me.
So, if I got this right, then the BIOS revision should be #401A0-0105.
Many thanks for your help, I appreciate that.

One more question. Should I replace the Dallas RTC battery before updating the BIOS?

Hi Wilius,

I understand your T2P4 has BIOS revision 0105 now, so you are shure in need of an update! 😉
This 0105 BIOS is probably the original version that came with the board and has never been updated.

You can flash the BIOS before or after replacing the RTC battery. This will not influence eachother.
But of course, with a flat battery the BIOS settings will not be retained.

Jan.

CPU Identification utility
The Unofficial K6-2+ / K6-III+ page

Go to top of page Go to top of page
Back to General Old Hardware
Close window
Close window