VOGONS


First post, by Intel486dx33

User metadata
Rank l33t++
Rank
l33t++

I was fooling around with the bios settings.
The motherboard PCChips 918i bios rev date 1994 does not officially support the AMD 5x86-133-P75.
and I was having ram and cache performance problems so I was fooling around with the timing settings and was able to get it to perform
better at ( Clk3 with timing=2-1-1-1 ) as it was using by default in auto settings ( Clk5 with timing=4-1-1-1 ).
but when I booted into Win95c it began to have issues and locked up.

So I said "Heck with it" and but in an officially supported CPU in the "Intel DX4-100".
But then that would not work either and did the same thing.
Only this time it would lock up at the boot screen right after listing the hard-drive.
it would seek the floppy drive but just lock up.
I checked all the drives one by one to eliminate any possibilities but no good.
I have seen this before and it was the Cache that was causing the problems or it could be that the capacitors have gone bad ?

Ever see this before ?

Last edited by Intel486dx33 on 2019-05-02, 16:42. Edited 1 time in total.

Reply 1 of 9, by meljor

User metadata
Rank Oldbie
Rank
Oldbie

Did you set the jumpers at the dx4-100 settings?

asus tx97-e, 233mmx, voodoo1, s3 virge ,sb16
asus p5a, k6-3+ @ 550mhz, voodoo2 12mb sli, gf2 gts, awe32
asus p3b-f, p3-700, voodoo3 3500TV agp, awe64
asus tusl2-c, p3-S 1,4ghz, voodoo5 5500, live!
asus a7n8x DL, barton cpu, 6800ultra, Voodoo3 pci, audigy1

Reply 3 of 9, by Intel486dx33

User metadata
Rank l33t++
Rank
l33t++

Actually, now that I recall. It was benchmarking fine in DOS 2.66 using Philscomputerlab benchmark tools.
So I think I will put the AMD 5x86 back in and confirm a stable build.
Then I will reinstall Win95c because I think the original install has become corrupt and was causing the lockup.

I looked for a Clear CMOS jumper but did not find one.
I checked the manual but did not see any listing of one.
So I just removed the battery and reinstalled.

Reply 4 of 9, by retardware

User metadata
Rank Oldbie
Rank
Oldbie

Lock up when accessing peripherals can also be caused by too-high ISA bus speed.
Try AT bus clock CLK/4 when testing whether the hardware has gone bad.

Reply 5 of 9, by Intel486dx33

User metadata
Rank l33t++
Rank
l33t++

Okay, I am back up and running with AMD 5x86 CPU.
Benchmarking and regression testing now to confirm best bios settings for a stable build.
So far so good.

Reply 6 of 9, by meljor

User metadata
Rank Oldbie
Rank
Oldbie

If you have set the jumpers for an AMD cpu it will not work correctly with an intel dx4.....

asus tx97-e, 233mmx, voodoo1, s3 virge ,sb16
asus p5a, k6-3+ @ 550mhz, voodoo2 12mb sli, gf2 gts, awe32
asus p3b-f, p3-700, voodoo3 3500TV agp, awe64
asus tusl2-c, p3-S 1,4ghz, voodoo5 5500, live!
asus a7n8x DL, barton cpu, 6800ultra, Voodoo3 pci, audigy1

Reply 7 of 9, by Disruptor

User metadata
Rank Oldbie
Rank
Oldbie
retardware wrote:

Lock up when accessing peripherals can also be caused by too-high ISA bus speed.
Try AT bus clock CLK/4 when testing whether the hardware has gone bad.

He has clocked the FSB at 40 MHz, so even CLK/4 is too much.
ISA Bus clock should be at 8 or 8.33 MHz.

Your 40/3 = 13.33 MHz has been very risky.

CLK/6 @ 50 MHz FSB
CLK/5 @ 40 MHz FSB
CLK/4 @ 33 MHz FSB
CLK/3 @ 25 MHz FSB
CLK/2.5 or CLK/3 @ 20 MHz FSB
CLK/2 @ 16 MHz FSB
Anything else overclocks the EISA or ISA bus.

Reply 8 of 9, by Intel486dx33

User metadata
Rank l33t++
Rank
l33t++
Disruptor wrote:
He has clocked the FSB at 40 MHz, so even CLK/4 is too much. ISA Bus clock should be at 8 or 8.33 MHz. […]
Show full quote
retardware wrote:

Lock up when accessing peripherals can also be caused by too-high ISA bus speed.
Try AT bus clock CLK/4 when testing whether the hardware has gone bad.

He has clocked the FSB at 40 MHz, so even CLK/4 is too much.
ISA Bus clock should be at 8 or 8.33 MHz.

Your 40/3 = 13.33 MHz has been very risky.

CLK/6 @ 50 MHz FSB
CLK/5 @ 40 MHz FSB
CLK/4 @ 33 MHz FSB
CLK/3 @ 25 MHz FSB
CLK/2.5 or CLK/3 @ 20 MHz FSB
CLK/2 @ 16 MHz FSB
Anything else overclocks the EISA or ISA bus.

So what “Clk” setting and timing do you recommend for a AMD 5x86-133-P75 overclocked to 160mhz. ?
Core v3.3
I have it set at 4x40mhz. = 160mhz.

So is a Clk/5 @ 40 MHz FSB with timing of 2-1-1-1
Is this okay ?

Reply 9 of 9, by Disruptor

User metadata
Rank Oldbie
Rank
Oldbie

CLK/5 is correct at 40 MHz FSB.
2-1-1-1 may work, but it is tight. You may have luck. Perhaps you need 1 write wait state. Be patient and don't draw conclusions too early.
Please report.

You can save the pictures from SST478 as pcx.
You can convert them to png and place them here.