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clh333
February 24th, 2016, 03:28 AM
In other posts I have described trying to make a PII motherboard (ASUS P2B98-XV) that originated on an HP Pavilion system - and has an HP BIOS - submit to the indignity of running Win95.

Particularly vexing has been the fact that the Phoenix BIOS only recognizes one "legacy" drive, and although it can be 3.5 or 5.25, DSDD or DSHD, there is no way to add a second. Tried supplemental controllers, etc., without success.

Finally I decided I had to update the BIOS. I got the latest BIOS from ASUS that was specific to this board as well as their flash utility, prepared a boot disk with the utility and the new BIOS code on it and tried to run the utility. Got an error message that the flash utility could not find the BIOS hook. Score one for HP?

Anyway, it occurred to me that if I could just burn another EPROM with this new ASUS BIOS code I could swap chips and try out the new "personality", as it were. But the little voice in my head keeps saying "It can't be that simple". So I'm asking here: What am I missing?

Thanks for your replies.

-CH-

Uniballer
February 24th, 2016, 04:07 AM
...I decided I had to update the BIOS. I got the latest BIOS from ASUS that was specific to this board as well as their flash utility, prepared a boot disk with the utility and the new BIOS code on it and tried to run the utility. Got an error message that the flash utility could not find the BIOS hook. Score one for HP?
-

Did you manage to run the "Save Current BIOS to File" option from AFLASH V2.21?



Anyway, it occurred to me that if I could just burn another EPROM with this new ASUS BIOS code I could swap chips and try out the new "personality", as it were. But the little voice in my head keeps saying "It can't be that simple". So I'm asking here: What am I missing?


The manual describes the BIOS update as also updating a "boot block" and "extended system configuration data" from the BIOS file. It might just be a linear burn into the EEPROM, but how would you know without a bit of reverse engineering the existing BIOS and corresponding file?

There is a chance you can find some info starting from the HP Pavilion xxxx model information, perhaps a discussion from users discussing BIOS upgrade options back in the day.

clh333
February 24th, 2016, 09:43 AM
Did you manage to run the "Save Current BIOS to File" option from AFLASH V2.21?

Could not get as far as the opening menu. Booted from a 3.5 disk - tried two different flavors of DOS - and avoided loading any drivers or AUTOEXEC commands. Get to an A: prompt and invoke AFLASH.EXE as instructed. Program loads and I get the following message: "ERROR! Can't Find System BIOS's Hook." Dumps me back out to DOS.

Not sure what version of AFLASH I have but the date is 12-16-02 4:41 PM and the size is 66,949.

As for the model of HP I can't recall, other than it was a Pavilion and in the 6 series, I think. The BIOS chip says "HPBV1" above "1.02". The chip is an ST 29EE... and the rest is covered by the sticker. I couldn't identify it through the HP web site and we all know how helpful their TS is once you are out of warranty. Hell, I think this board is older than some of their Level 1 Support people.

Thanks for your reply,

-CH-

Chuck(G)
February 24th, 2016, 10:05 AM
You do realize that the on-board SuperIO chip may not be capable of supporting more than one floppy drive, don't you? And the southbridge setup may permanently reserve IRQ 6/DMA 2--even if you disable FDC support in the BIOS? I've run into this on several boards.

clh333
February 24th, 2016, 11:15 AM
You do realize that the on-board SuperIO chip may not be capable of supporting more than one floppy drive, don't you? And the southbridge setup may permanently reserve IRQ 6/DMA 2--even if you disable FDC support in the BIOS? I've run into this on several boards.

I have suspected as much but don't know how to confirm it. I can and have disabled the BIOS' FDC support and substituted a PCI controller card, but either I never got the configuration right (always a possibility) or the card and the BIOS simply would not coexist. Either the machine would hang during boot or would come up but not recognize the drives, depending on what was enabled and disabled.

The chipset is Intel 440BX - I know this from the MFR specs - but I can't see IDs because of the honking big heatsink on the PII. Is there a way to query the chipset for IDs?

Thanks again,

-CH-

clh333
February 24th, 2016, 12:18 PM
From the Device Manager: (see attached). Could find but could not run an Intel utility to identify chips; missing DLL, utility runs XP and higher.

-CH-

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Stone
February 24th, 2016, 12:35 PM
Have you tried CPU-Z?

clh333
February 24th, 2016, 02:27 PM
Who?

-CH-

Chuck(G)
February 24th, 2016, 03:56 PM
The chipset is Intel 440BX - I know this from the MFR specs - but I can't see IDs because of the honking big heatsink on the PII. Is there a way to query the chipset for IDs?

Why not just remove the PII temporarily and read off the big chips on the motherboard?

I don't much care for HP Kayak and Pavillion PIII-era motherboards. They're usually some depopulated board that HP got a great deal on and have all sorts of shortcomings. Better to find a motherboard from a PII/PIII era Vectra. Those are generally pretty decent.

clh333
February 25th, 2016, 02:13 PM
Have you tried CPU-Z?

Thanks for your suggestion: I was unaware of the utility. Very impressive, but does not run under Win95.

-CH-

Stone
February 25th, 2016, 03:06 PM
How about Aida32, Sisoft Sandra or Everest?

clh333
February 27th, 2016, 08:10 AM
Why not just remove the PII temporarily and read off the big chips on the motherboard?

Chuck,

Thanks for the suggestion. I can get the processor out of its slot but can't figure out how to remove the heatsink support which seems to be attached to posts on the mobo and is obscuring what I think is the northbridge.

See attached page from the ASUS manual, illustration on the lower left shows the support.

-CH-

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clh333
February 27th, 2016, 10:57 AM
How about Aida32, Sisoft Sandra or Everest?

Thanks for your suggestion. Both Aida and Everest ran on the one-hamster Win95 machine and both were impressive in the amount of detail they presented, although a few times I had to check to see if the machine had frozen. Each did a little better in one area or another, but if I had to pick one it would be Everest.

Everest identified the CPU and motherboard in better detail, as an example, and identified the chipset (northbridge) as Intel 82440BX/ZX. No word on a southbridge or SuperIO, except to say "Standard Floppy Disk Controller, DMA 02, IRQ 06, Port 03F0-03F5, Port 03F7-03F7."

-CH-

Chuck(G)
February 27th, 2016, 11:45 AM
The posts themselves are more-or-less permanently attached to the motherboard--don't remove them. However, if you look carefully, they usually have locking tabs that engage the PII heatsink. Just push the "posts" apart slightly and the PII with heatsink will slide right out.

clh333
February 28th, 2016, 05:01 AM
The posts themselves are more-or-less permanently attached to the motherboard--don't remove them. However, if you look carefully, they usually have locking tabs that engage the PII heatsink. Just push the "posts" apart slightly and the PII with heatsink will slide right out.

You're right, I don't want to pry out the posts. The attached pics may illustrate the problem better: I can remove the CPU and the heat sink with it by pushing in on two tabs and lifting the processor out. With the processor and heatsink removed you can see there are six posts. Four of them attach the "towers" that the CPU/HS slide into and stabilize the CPU in its mobo slot (A). The other two hold in place a low support for the heatsink; sot of a stabilizer (B). I can see that the bar is sitting on the post but I don't know what to do to detach it. Ever seen anything like this?

Thanks,

-CH-

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