What exact CPUs are you using?
Did you try swapping their positions?

I am using at the moment two Pentium-s 1266
One SL5QL and one SL5LW (could be this the problem?)
Will try to swap them.

They're both tA1 stepping but I still wouldn't rule out the different part numbers as your problem.

Doornkaat wrote on 2023-04-01, 20:11:

They're both tA1 stepping but I still wouldn't rule out the different part numbers as your problem.

I changed them for my two 1400 chips.
Same story, only one cpu show up at post, but the voltage reading is there inside the bios.

On AIDA64 I see both processors but one is “disabled by user” ????

Please help….

Check your msconfig if "number of processors" is altered.

Mamba wrote on 2023-04-02, 15:46:

Same story, only one cpu show up at post, but the voltage reading is there inside the bios.

When I only have one CPU installed I see voltage readings for coth CPUs. This is expected as the voltage is still present the SIO chip will report it.

Mamba wrote on 2023-04-02, 15:46:

On AIDA64 I see both processors but one is “disabled by user” ????

When things are not as expected I feel it's wise to check what another utility reports and wonder what my SIV utility would report.

When I looked on one of my systems it reported No CPU Installed which makes me suspect one of your CPUs is disabled in the BIOS. Can you enable it? What happens if you do a "clear CMOS"?

bofh.fromhell wrote on 2023-04-02, 16:11:

Check your msconfig if "number of processors" is altered.

I see only one processor at boot.
It is not a Windows issue.

red-ray wrote on 2023-04-02, 16:23:

When things are not as expected I feel it's wise to check what another utility reports and wonder what my SIV utility would repo […]
Show full quote

Mamba wrote on 2023-04-02, 15:46:

On AIDA64 I see both processors but one is “disabled by user” ????

When things are not as expected I feel it's wise to check what another utility reports and wonder what my SIV utility would report.

When I looked on one of my systems it reported No CPU Installed which makes me suspect one of your CPUs is disabled in the BIOS. Can you enable it? What happens if you do a "clear CMOS"?

Clear cmos already done, bios updated, same behaviour.
I do not see a bios function of field to enable/disable one of the CPUs

But on PC Health status screen of the bios I see both CPUs.
It is really weird!!

Mamba wrote on 2023-04-02, 16:26:

But on PC Health status screen of the bios I see both CPUs.

When I only have one CPU installed I see voltage readings for both CPUs. This is expected as the voltage is still present the SIO chip will report it.

1. Post the [Machine] screen shot.
2. If you remove the 2nd CPU what does [Machine] report for it?
3. Which version of Windows is installed?
4. What HAL is installed (press [Windows] to check), I would expect HAL ACPI 1.0 - APIC platform MP or HAL MPS 1.4 - APIC platform.
5. What is in boot.ini, post it.
6. What is in the MPS table, post Menu->Hardware->BIOS Tables->MPS

red-ray wrote on 2023-04-02, 16:42:

When I only have one CPU installed I see voltage readings for both CPUs. This is expected as the voltage is still present the SI […]
Show full quote

Mamba wrote on 2023-04-02, 16:26:

But on PC Health status screen of the bios I see both CPUs.

When I only have one CPU installed I see voltage readings for both CPUs. This is expected as the voltage is still present the SIO chip will report it.

1. Post the [Machine] screen shot.
2. If you remove the 2nd CPU what does [Machine] report for it?
3. Which version of Windows is installed?
4. What HAL is installed (press [Windows] to check), I would expect HAL ACPI 1.0 - APIC platform MP or HAL MPS 1.4 - APIC platform.
5. What is in boot.ini, post it.
6. What is in the MPS table, post Menu->Hardware->BIOS Tables->MPS

Let’s not focus on Windows, the HAL is not an issue, I have two disks with the same OS installation, one for multicore and one for single core. Only the latter works.

The cpu is not recognised during post.
Will add some screenshots with and without it

red-ray wrote on 2023-04-02, 16:23:

When I only have one CPU installed I see voltage readings for coth CPUs. This is expected as the voltage is still present the SI […]
Show full quote

Mamba wrote on 2023-04-02, 15:46:

Same story, only one cpu show up at post, but the voltage reading is there inside the bios.

When I only have one CPU installed I see voltage readings for coth CPUs. This is expected as the voltage is still present the SIO chip will report it.

Mamba wrote on 2023-04-02, 15:46:

On AIDA64 I see both processors but one is “disabled by user” ????

When things are not as expected I feel it's wise to check what another utility reports and wonder what my SIV utility would report.

When I looked on one of my systems it reported No CPU Installed which makes me suspect one of your CPUs is disabled in the BIOS. Can you enable it? What happens if you do a "clear CMOS"?

Are you saying that you see temperature of your non present CPU?
Sorry but I think it is a bit strange...
You cannot see temperature of a thing that is not there.
I can see voltages AND temperature, see the screenshots above.

Did anyone before me suggest that you try at first only 1 CPU in 1st and later in 2nd socket to see if both socket work?

BoYan wrote on 2023-04-02, 18:16:

Did anyone before me suggest that you try at first only 1 CPU in 1st and later in 2nd socket to see if both socket work?

Yeah, have two pairs. All 4 work.

Mamba wrote on 2023-04-02, 18:08:

Are you saying that you see temperature of your non present CPU?

I had not said so, but yes I do. It's not strange at all as I suspect the temperature sensor is part of the motherboard so there does not need to be a CPU there for a temperature to be reported.

Surely you checked what happened to it when you unplugged the 2nd CPU, did you?

Further why do you have two OS installations? The same one should work for both one and two CPUs.

It would be much easier/possible to better help you if you posted the information I asked for, epically so what is different on [Machine] when one and two CPUs are installed.

red-ray wrote on 2023-04-02, 18:26:

I had not said so, but yes I do. It's not strange at all as I suspect the temperature sensor is part of the motherboard so there […]
Show full quote

Mamba wrote on 2023-04-02, 18:08:

Are you saying that you see temperature of your non present CPU?

I had not said so, but yes I do. It's not strange at all as I suspect the temperature sensor is part of the motherboard so there does not need to be a CPU there for a temperature to be reported.

Surely you checked what happened to it when you unplugged the 2nd CPU, did you?

Further why do you have two OS installations? The same one should work for both one and two CPUs.

It would be much easier/possible to better help you if you posted the information I asked for, epically so what is different on [Machine] when one and two CPUs are installed.

Here what I see with two cpu, the second cpu is not properly recognised (no matter which I put, is the same).

MPS 1.4

Maybe a stupid question, but I see your Satan Inside BIOS image, what about trying with a stock BIOS to rule out another variable?

Minutemanqvs wrote on 2023-04-02, 18:35:

Maybe a stupid question, but I see your Satan Inside BIOS image, what about trying with a stock BIOS to rule out another variable?

It was exactly the same with the stock bios.

Here with one cpu installed.

Same but there is no temperature reading for second cpu.
With only one cpu the system boots faster, it makes sense as it won’t lose time in trying to recognise the second cpu.

Here a picture of the socket, could it be that the recap was not perfect for capacitors close to it?
How can I check?