thermal tables

[Fris]

I need some expert counselling. The problem is that my CPU fan does not come on until the temp sensor is >70C but freezing and shutdown problems begin occurring at 60-65C (not to mention a burning odor). Hardwiring the fan to 5V so that it is constantly on keeps the CPU temp at 30C lightly loaded, 50C under heavy load with no crashes.

So what I'd like to do is modify the thermal tables in the BIOS but I'm at a loss of how to go about doing this.

Background

As some may remember, HP screwed over a large number of people with their ZE1000 laptop series several years ago. They had problems with overheating and HP placated their customers by tying up these laptops in service shops during the warranty period and then dropped support. I'm one of those.

Here are the stats on my system:

1.) Top three lines of boot screen:
Insyde Software MobilePro BIOS v3.00.03
HP Pavilion BIOS version JA.M1.31
VIA VT8362 Athlon K7 BIOS 3.00.03
(there is *no* BIOS ID string)
2.) System info probe:
Technology code GE: VIA KN133 + VT8231
Chipset: VIA 82C305 rev 128
North Bridge: VIA Pro Savage Pn 133T
South Bridge: VIA VT8231
Display controller: S3 Savage 4 in North Bridge
Audio controller: VIA/Realtek ALC201 AC97 Codec
CD player controller: O2 OZ-163
LAN: Realtek RTL8100L
CardBus controller: ENE 1410
Keyboard/embedded controller: National NS87591
Super I/O: in South Bridge
Superio: Winbond 877TF (use 87h) rev 0 found at port 3F0h
Superio: Winbond 877TF (use 86h) rev 0 found at port 3F0h
3.) More info:
chip is a 39SF040, PLCC type

What I've learned:

1.) Searching the net, there is virtually no (published) experience with modding Insyde's BIOS
2.) Insyde software says they won't help me, call HP
3.) HP laptop support says they can't help me, call a service center
4.) HP service center says they'll help me at considerable cost ($800 gut replacement) but the problem is not guaranteed to be solved beyond 90 days
5.) called esupport who said he will not touch those, Insyde's bios is unbreakable and so is the relationship between that bios and the motherboard.
6.) the ROM file is unrecognized by Phoenix BIOS editor and other editors
7.) Everest shows that thermal control is not supported (I do get a temp sensor)
8.) examining the registry in XP, there are only a few devices under control in the ACPI namespace (as opposed to 5-15 on my other computers)
9.) so tried Intel's ACPI dissassembler to extract the DSDT (iasl -d) but, of course, it doesn't see any ACPI support
10.) I can retrieve _PASV (which is set at 90 degrees Centigrade!) but can't retrieve any other variables
11.) yes, ACPI hoopla including thermal zone appears in XP's device manager but that doesn't mean anything
12.) Debian with 2.6.12 kernel can't provide thermal control either, which makes sense
13.) deleting ACPI from device manager or reinstalling XP does not help, neither does APM, the fan stays quiet even in DOS until the laptop is HOT
14.) there are no BIOS settings to change, unless you enjoy changing the system time or boot order
15.) I have yet to go to Usenet, my last resort. I suspect if I can't find a hint of an Insyde editor or experience on the web, I probably won't find it there.

So it appears that thermal control is isolated to the BIOS. I know enough to extract the fan module from the diagnostic executable on HP's hidden partition (eDiag tools), dissect the code out that tests the fan and turn it on but the ideal solution is to attack the graded motor control conditions in the BIOS. I could decompile the .rom with IDA Pro but my textbooks on assembler are from the eighties and it has been nearly as long since I've worked at this level. I found that even the great Borg on one forum (in German) said that is the only way of dealing with this BIOS that he was aware.

My suspicion is that there is a BIOS out there that has been used for this chipset on other machines that I can drop in and solve my problems. I might lose the tattoo and have to load up a different copy of XP but that is fine. I've ordered a blank 39SF040 and will send it and mine to someone who can make me a copy to play with but I would like to know if anyone can solve my problem with a minimum of pain. I apologize for the long post but I hope it pre-answers any questions, and feel free to move this to another forum if it isn't sufficiently technical.

Thanks,

Brad