40GB : 06/21/96-i430FX-2A59CV3NC-00

BIOS update, EIDE card, or overlay software? (FAQ Hard disk recognition)
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cp
BIOS Guru
Posts: 1914
Joined: Mon Oct 21, 2002 9:07 pm
Location: Germany

Hi!
I recently bought a bunch of old S7 boards..including a PcPartner S7 i430FX board. Funny thing about this is: PcPartner site (http://www.pcpartner.com/support/bios/i430.htm#fx) says: it's a MB500N (checked the manuals for pictures, my board has 35-8212-33 silkscreened on it). BIOS available on the PcPartner site for the MB500N (same as the MP5-TRI and MB530N) is older than the BIOS on my board PcPartner: 60313, mine: 60621, also check the release date!). Flashing the BIOS from the PcPartner site makes the floppy stop working on my board (YES, i chose the correct BIOS from the archive..SMC I/O).
And now for some more funny things: although my BIOS is one of the infamous Award 4.51PG it doesn't crash on 40GB HDD detection! it displays the wrong size instead (8GB..looks like a wraparound from 32GB limit as 32GB+8GB=40GB..poor little counter ;~)).

So...if someone could please get hands on that original BIOS of mine and fix the detection bugs (32GB and 64GB if possible). I put an archive containing the BIOS filehere.

If you have any further questions feel free to contact me. And thanks in advance for your efforts!
cp
KURIAKI
Moderator
Posts: 1037
Joined: Thu Nov 18, 2004 9:37 pm
Location: Cancun, Mexico

Searching for Main Block...Found at 0
Searching for end of last block...Found at 81103
Decompressing Main Block...Decompressed 71467 bytes into 131072 bytes
BIOS ID string: 06/21/96-i430FX-2A59CV3NC-00
BIOS OEM string: BIOS (60621)
INT13h Extensions...Not present
=> Code not found: BIOS does not support HDDs up to 32GB!
Patching 32GB bug failed!
More than 100,000 BIOS strings in my database just now!
http:/ /www.kuriaki.has.it/
http:/ /www.supportbios.info
------------------------------------------
Saludos desde Cancun, Mexico
KURIAKI
cp
BIOS Guru
Posts: 1914
Joined: Mon Oct 21, 2002 9:07 pm
Location: Germany

Okay, this is what i've found out so far:
BIOS Autodetection will detect 8.4GB if the drive is larger than 8.4GB (in all modes LBA,Normal,Large). If the drive is smaller it will be detected with its correct size.

By setting CHS values by hand, it's possible to overcome the 8.4GB autodetection barrier. Setting Heads to '64' gives a size of 32GB, every value above 64 will crash the BIOS. When setting the Head value above 16 in the BIOS (with C and S already maxed out) the size of the HDD isn't shown correctly..it says 'Q822' when it should be 32GB. But the POST screen will show the correct size.

I think it's possible to remove the autodetection bug and the 32GB HDD limit by adding a custom patch. So if someone could get the assembler-hands on this one providing another patched BIOS for the community..
ajzchips
El cheapo dude
Posts: 3048
Joined: Sat Mar 23, 2002 12:41 pm
Location: Madrid, Spain

Adding true BIOS support for HDDs above 8GB requires redoing the kernel. It is not easy at all...
If it does support (true support, not just the size display) HDDs upto 32GB, then patching it is relatively easy.
cp
BIOS Guru
Posts: 1914
Joined: Mon Oct 21, 2002 9:07 pm
Location: Germany

Okay, after doing some extended reading i guess there's no easy way to come around the BIOS autodetection limitation. As far as i can get it the BIOS supports HDDs upto 64GB but the autodection mechanism does not go over 8.4GB (C/H/S 16383/16/63). Looks like the BIOS doesn't use the Extended INT13 to get the C/H/S values from the drive.

Anyway there is kind of a workaround for this: manually setting the values.
C/H/S 65535/16/63, 16383/64/63, 8191/128/63, ... work. Even setting the values manually to something like C/H/S 7967/255/63 (64GB) works fine. Anything above this will crash the BIOS.

So i guess even if someone would fix the autodetection mechanism to use a Heads value of 255 all the time the BIOS would not be able to detect HDDs correctly (because of the lack of Ext Int13 detection). Please correct me if i'm wrong! Next thing would be the removal of the 64GB barrier but i guess that would be too complex and not worth the effort.
Yaye
BIOS Rookie
Posts: 53
Joined: Tue Jan 10, 2006 3:12 am
Location: Near Milan, Italy

Can you look at my topic please?
http://www.wimsbios.com/phpBB2/viewtopic.php?t=7995

I need the manual for a similar board!

Thanks
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