cpu cooling?

Present 😉
heatsink and fan.
I have another CPU am5x86 133 but can not find jumper settings to test...

Any chance your VLB bus is set to 40mhz or 0 wait states and your video card / initial I/O card just can’t handle it? Try 33mhz / 1ws?

VLB is set to 33Mhz and 0 wait states, but set to 1 do not change anything. I just install DOS 5.0 and it is maximum stable in it. Zero hangouts zero errors. Problems start in WIN95 installer. Tomorrow (in europe) I will try to do some screenshots from BIOS settings and errors.

I take it is stable in DOS. Are you sure you have the CPU jumpers set proper ? Have you run a Memtest ? Windows 9x is very good at puking on bad ram 😀
Can you post a picture of the board with the current ram ?

Hi,

Today update:
1. I found some PINs on mobo marked TURBO_SW with no jumper set- set it to disable. It help with stability. I run some benchmarks from DOS, but I do not know why there is so small difference between ISA and VLB IO card in HDD test, any ideas?

ISA I/O:

VLB I/O:

Benchs (TheLazy1, are you still here? 😉):

2. I can't run Memtest and I do not know why, maybe because of version (4.2 from floppy disk), it only reboot all computer, no even turn on.
3. After set turbo to disabled, WIN95 install successfully but it is not the end of problems, error shows during first launch,

here is te screen:

and after key pressing:

4. Can anybode tell me what are those options means and how to set them right, please?
-Hidden refresh
-Fast reset emulation
-Latch local bus
-Local BUS ready

Are these settings correct?

And the view of installed items:

P.S. Benchmarks was running with 40Mhz CLK and 3x multiplier, but next I set it to default (33x3).

Thank You

Return 0; wrote on 2022-08-29, 22:48:

2. I can't run Memtest and I do not know why, maybe because of version (4.2 from floppy disk), it only reboot all computer, no even turn on.

Memtest86+ v4.10 is the last version that supports 386 and 486, that is the version I use for 486. v4.20 up requires Pentium.

Is CPU Voltage correctly set up ? (DX4 needs 3.3V)
Try to play with cache settings (WB vs WT).

Memtest:

Is CPU Voltage correctly set up ? (DX4 needs 3.3V)
Try to play with cache settings (WB vs WT).

Yes, I try with both 3.3V and 3.5V set with no effect... I can only L2 cache settings change and one of them doesn't work at all.

This Windows error always occurs at the same time.

Problem solved: new CPU on board and working great.

New question is why extended memory speed is so small? Is that normal bandtwith (19-21MB/s)? Please Look at speedsys screen.

Which CPU do you use now?

I guess your cache and memory settings are poor ot fail safe.

Not all Intel DX4 support Write Back cache - only a few.

You had Intel 486 DX4 100 and overclocked it to 120. That's why you failed to install Windows. It wasn't stable. Get an AMD 5x86 133 and a 2GB hard drive. 425MB was used for 486 DX2. Conner HDDs were slow, that's why you're getting so poor performance. Get a Western Digital HDD. Install 32MB RAM and you have a great 486 rig.

Hi, it was a long story...

At first, I solve the problem with memory speed. My mainboard do not support an DirtyTag but I modify my BIOS and update It. After this, memory bandtwidth grow up to 135MB/s on WriteBack mode.
Yes I know only few iDX4 support Write-Back cache but the internal cache. I have the &EW one.

The second is that my 5429 CirrusLogic card is working great on 50MHz 0WS with Am5x86 but! The CPU in this configuration (50x3) is slower than on 40Mhz (x4).

the last one: I can not start any ISA HDD controller because of hanging out on floppy disk read or hard drive read. In best cause shows up something like :"Change system disk and press enter". And this problem is related with my fantasy:
From few weeks I have POD83 and I'm trying to start it on 40MHz. Main problem is Local Bus Ready in BIOS, working only on Synchro, If I set to Transparent the system is hanging on POST (I think because of VLB I/O, but this is not occure when 5x86 is installed). ISA I/O do not work- like before.

Any ideas how to start with ISA I/O? I hope It start with 100MHz POD and 150MHz am5x86 on best performance sttings.

I am Greatfull for your help!

That ram speed doesn’t sound right. Could that be the cache speed?

In Speedsys it called "Memory bandwidth" other params:
Read: 47
Write: 76
Move: 17

L1/L2:
R: 151/68
W: 76/76
M: 196/35

My test’s results shows that floppy drive do not work with POD83, no matter it is VLB or ISA controller, it is 33 or 40MHz bus.

System is going through POST and after that on screen I can see „invalid system disk, change disk and press enter”. When I put win bootable disk then drive is rotating few times and hang-on.

Only on POD83 CPU.

Clear cmos?

Try a gotek?

Try lower fsb?

There are a few pin tricks on the pod you could try but that doesn’t seem related.. but out of all my ideas I think lower fsb and clearing cmos is best bet.

There is also the very real possibility of a false correlation randomly failing disk drive happens to occur when you are running the pod but isn’t actually related. In which case: gotek

Thank you for answer.
I will try with 25Mhz fsb but it is under base 33.
Any idea why with Am5x86 everything is OK, even on 50Mhz?
My only idea is jumper setting for CPU type, but it is set like in manual...

Hard to say. You may be dealing with a glitch not a improper setting.