Oh dear, this could be a problem. I ran the Award utility called Flash465, which has an era appropriate release date of 06/28/1995, and when I run this util, it displays an error message which says "System BIOS does not have Flash support". I am curious that there is a lack of flash BIOS jumpers on the mobo. Does that mean that I am stuck with the initial BIOS release for this board, which may possibly not fully recognise and support the P75 CPU?

Ugh, if that's true then this is bad. I suppose I could somehow get a new BIOS chip, that's got the updated BIOS on it. But how can I do that? I guess I could get an Award BIOS chip from somewhere, and then hot flash it with the latest BIOS file. Would that be a good idea? Thanks a lot for any advice on this, because this is important. I really want to get this P75 running to the max on this board, to see if it can come close to a P75 @ 200 MHz on a PCI 486 mobo.

These boards don't have flashable BIOS chip, I hired some german dude to flash mine back when I was fiddling with these Asus boards

Amigaz wrote:

These boards don't have flashable BIOS chip, I hired some german dude to flash mine back when I was fiddling with these Asus boards

Ah, I see. So that's the only way then. Do you know if it's possible to remove the BIOS chip on this board, and put it in to another "more advanced" mobo, and hot flash it that way? I mean, what I am trying to say is this: is it possible to flash the BIOS chip found on this Asus mobo, but not using the Asus board, because there is no support for flashing on this board, but on another board, that does allow BIOS chips to be flashed? Or, is the actual BIOS chip on the Asus board completely "read only", that is to say, it cannot be flashed at all, no matter what mobo you put it in to? Thanks a lot for any further advice on this! 😀

Those ROMs can not be written while installed on the motherboard. You need an EPROM programmer, or someone who has one.
I can confirm that with the latest Bios, the speed of 200 MHz is correctly displayed.

I think your VLB graphics card causes the low Quake score. S3 805 is a very old chipset. You were using a S3 Virge card for your PCI system? Results would be more comparable with a more recent VLB S3 card

BastlerMike wrote:

Those ROMs can not be written while installed on the motherboard. You need an EPROM programmer, or someone who has one.
I can confirm that with the latest Bios, the speed of 200 MHz is correctly displayed.

Thanks very much for this info. Do you know if the Willem programmer, which can be found easily on ebay, will be OK? Also, if I successfully flash the BIOS chip, will it also allow me to run the P75 CPU in write-back mode? If possible please, can you run ChkCPU.exe, and tell me what it says? Does it say "write back mode" for your P75 - that's assuming you are using one, of course! 😀

Also, I messed about with the BIOS timings, and I also set the mobo's jumper to VESA wait state = 0, and I can get SpeedSys to score 64.something, which isn't too shabby! I can also get full screen Quake timedemo to score 14.1, which is also fairly good. My best PCI Quake score is 18.3, however. But, if I can get the P75 to run in write-back mode, then these scores will increase.

But the other bit of bad news is that SpeedSys did not show me any reading for L2. I wonder if it has disabled it, because my BIOS timings were too aggressive? Also, on the mobo, I set the "Delay jumper" to "no delay", and the mobo didn't POST, so I set that jumper back to "delay". BTW, this jumper is different to the VESA wait state jumper.

I have a self-built programmer, but it is not working anymore 😢
Maybe I should consider to buy such a Willem thing...

Hmm. Yes, maybe! 😀 I changed the RAM on the mobo, and I also messed about with the BIOS timings a bit more. My full screen Quake timedemo score is now 15.1. It's getting faster! I have a bunch of VLB cards here. I might try them all, and see which ones work at 200 MHz, and also see if they improve the Quake score, or not.

Speedsys - it's quite fast, but no L2. ATM, I don't know why this is.

BIOS timings - I think they are set to their fastest possible?

I tried an ATI Mach64, but it wouldn't POST. Also, I tried another 86C805 card, this time an STB Powergraph. It was slower than the first 805 card I tried, which was made by DEC. Also, I've just noticed that this VLB mobo has a PS/2 header on it! Yay! 😀

Amigaz, is your board the revision 2.1 model? Also, please can you tell me the website of the German dude? Finally, are you using your 2.1 (?) board in one of your "production machines"?

BastlerMike, please can you explain why the hot flash technique cannot be used for these BIOS chips?

Thanks a lot people.

Edit: I just noticed that if I set the BIOS timings to their slowest values, SpeedSys still does not report any L2 being used. My guess is that the BIOS needs upgrading, before it can work fully with the P75 CPU. I mean, even the online manual from Asus doesn't mention any settings for the P75. I guess this manual was for the original board release, and also I have the original BIOS release.

Have you got a jumper over the turbo pins on the motherboard? Some boards disable cache if turbo is disabled.

DonutKing wrote:

Have you got a jumper over the turbo pins on the motherboard? Some boards disable cache if turbo is disabled.

That's a good point. There is a jumper on the turbo pins, but just as an experiment, I removed it, to see if the turbo functionality was in some way "reversed" on this board. My tests then ran more slowly, so I replaced the jumper on the turbo pins.

At the moment, I continue to use the DEC 805 VLB card, because I don't have a good choice of VLB cards at my disposal. I thought I had, but I was mistaken. With the system maxed out, but L2 not operational, I ran 3DBench and was pleased that the score "went off the scale", and read: 0.00. Consequently, I ran 3DBench2, and got a score of 99.6. (My best 486 PCI score is 118.1) Any 486 VLB'ers out there want to try and beat 99.6? I'm sure you can! 😀

Edit: I've learnt something about this mobo today. If I completely "max it out", and then switch it on, it won't POST. To get around this, I hit the reset button, and everything's OK. This sequence of events happens every time.

Can I double-check these jumpers settings please? I've tried another CPU, this time an Intel DX4-100 writeback (&EW) CPU. ChkCPU.exe reports that the L1 is write-through. ChkCPU.exe also reported the same thing, for the AMD P75 CPU. Also, just like the P75, SpeedSys does not show that L2 is functioning when I use this Intel CPU. Here are my jumper settings for the Intel DX4-100 &EW CPU:

JP16 1-2
JP17 1-2, 5-6
JP18 1-2
JP19 1-2, 3-4, 5-6
JP20
JP21
JP22 1-2, 4-5

These settings can be seen on this webpage, here. They are in the top left box. Either I have got these settings wrong, or I *must* upgrade the BIOS in order to get CPUs with write-back cache working. However, the "old" online manual available on the Asus website (inside the socket 5 folder) does mention CPUs with L1 write-back cache, so this adds to my confusion as to why this isn't working correctly.

Edit: BTW, the P75 jumper settings I used were:

JP16 1-2
JP17 1-2, 5-6
JP18 1-2
JP19 1-2, 3-4, 5-6
JP20 1-2
JP21
JP22 1-2, 4-5

These settings can be seen in the webpage mentioned above. They are in the bottom left box.

When I use the jumper settings mentioned on that site, my L2 cache is also not recognized. There must be something wrong.
My settings are:

JP16 1-2, 4-5
JP17 1-2, 5-6
JP18 1-2, 5-6
JP19 1-2, 3-4, 5-6
JP20 1-2
JP21 3-4
JP22 2-3, 4-5

It seems to be important that JP21 is set to 3-4 !

Thanks a lot BastlerMike! 😀 Are these settings for the P75, or for the Intel DX4-100 &EW? I tried these settings for the DX4-100 &EW, but I got no BIOS POST on the screen.

Success! I'm sorry about my post, immediately above. I think there is something wrong with this mobo. When I switched on power, I saw no BIOS POST. I switched off power, then tried again a few minutes later. It now works, and ChkCPU.exe reports that the CPU is running in write-back mode.

Edit: Now that this works, I will change the jumpers, and try the P75 again. I wonder if this jumper change is simple? Perhaps I only need to change one jumper setting? Do you know which jumper(s) I need to change, in order to use the P75? Thanks a lot!! 😀

My jumper settings from above are for P75 CPU 😉
They are the same for the iDX4-WB, except JP20 1-2. This jumper sets the multiplier and should be removed when using the Intel CPU.

Thanks very much for your help! 😀 I will try the P75 very soon, and report back with my test results! 😀

I tried the P75 with the settings above, but unfortunately the system freezes at the BIOS POST stage just before the message "Starting MS-DOS..." should appear on the screen. I have noticed this happens, when I configure CPU type jumper settings that the mobo appears to be confused about.

Because the settings supplied by BastlerMike must be correct for the P75, I can only assume that the reason for this "freezing" is due to my older BIOS. Also, the BIOS POST reports that the P75 is an AMD DX4 S, running at 120 MHz. Damn, if only I had the latest BIOS. I am reluctant to buy a Willem unit, because if I did and it fried my chip, I'd be in an even worse position!

I've just had a look inside my "box of junk", and I have found 2 Award BIOS chips. They were taken from 486 mobos, and their stickers both say: "486DX".

I appreciate that I must peel back both of these stickers to reveal important information, and also peel back the sticker on the BIOS chip in the VLB 486 mobo for the same reason, but I wonder - what is my chance of success, if I use one of these spare chips, inside the Willem flash device? About 10%, about 50%, or about 90%? Is it impossible to say? Thanks a lot for any advice on this subject!

Edit: I still don't understand why the option of hot flashing the BIOS chip inside a more modern mobo appears to be unavailable.