[SOLVED] Switched CPU's, no display - "weak" power - front panel lights won't switch on

aqgon_6

Commendable
Mar 1, 2018
23
0
1,510
Hello everyone,

As your forums never failed to provide me with valuable advice, and as someone who is far from being an expert, I would like to request your help one more time:

Basically, I bought a Celeron PC in a yard sale, and at the time I cleaned it the best that I could, and I proceeded to format it and use it for about 3 years. I can't remember why, but I installed a power supply that came from a Pentium IV at the time.

Given that the PC was always loud and had a slight old cupboard type smell, even after the cleaning, last week I decided to change the heatsink and cooler, and took the opportunity to change from this Celeron 600mhz to a Pentium III 866mhz.

I couldn't confirm what my motherboard was, I'm 90% sure it is this obscure model: http://www.motherboard.cz/mb/sg/SG-APP133AB3.htm

I got the new CPU today, so I dismantled the case and gave a deep clean to the power supply, case and components, removed the heatsink, cooler and Celeron CPU, and put the new CPU in. As I am still waiting for the heatsink, cooler and thermal paste to arrive, I just wanted to do a quick boot with only the CPU in the socket to confirm that the Pentium III 866mhz was recognised, and turn off the PC immediately.

Unfortunately, the computer turns on but I got no image, and it's almost as if the motherboard is underpowered, the front panel lights of the case don't even turn on, and the power supply is very "chill" and quiet in its activity.

Later I switched to the Celeron again, with only the CPU in the socket as well, and got the same thing.

Did I:

1. Fry the CPU by turning the PC on without thermal paste and heatsink?

2. Did something to the power supply when I cleaned it?

Do you think you can help me with this? Thank you so much for your time and your attention.

Best regards,
André
 
Solution
Hello everyone,

As your forums never failed to provide me with valuable advice, and as someone who is far from being an expert, I would like to request your help one more time:

Basically, I bought a Celeron PC in a yard sale, and at the time I cleaned it the best that I could, and I proceeded to format it and use it for about 3 years. I can't remember why, but I installed a power supply that came from a Pentium IV at the time.

Given that the PC was always loud and had a slight old cupboard type smell, even after the cleaning, last week I decided to change the heatsink and cooler, and took the opportunity to change from this Celeron 600mhz to a Pentium III 866mhz.

I couldn't confirm what my motherboard was, I'm 90% sure it is...
Hello everyone,

As your forums never failed to provide me with valuable advice, and as someone who is far from being an expert, I would like to request your help one more time:

Basically, I bought a Celeron PC in a yard sale, and at the time I cleaned it the best that I could, and I proceeded to format it and use it for about 3 years. I can't remember why, but I installed a power supply that came from a Pentium IV at the time.

Given that the PC was always loud and had a slight old cupboard type smell, even after the cleaning, last week I decided to change the heatsink and cooler, and took the opportunity to change from this Celeron 600mhz to a Pentium III 866mhz.

I couldn't confirm what my motherboard was, I'm 90% sure it is this obscure model: http://www.motherboard.cz/mb/sg/SG-APP133AB3.htm

I got the new CPU today, so I dismantled the case and gave a deep clean to the power supply, case and components, removed the heatsink, cooler and Celeron CPU, and put the new CPU in. As I am still waiting for the heatsink, cooler and thermal paste to arrive, I just wanted to do a quick boot with only the CPU in the socket to confirm that the Pentium III 866mhz was recognised, and turn off the PC immediately.

Unfortunately, the computer turns on but I got no image, and it's almost as if the motherboard is underpowered, the front panel lights of the case don't even turn on, and the power supply is very "chill" and quiet in its activity.

Later I switched to the Celeron again, with only the CPU in the socket as well, and got the same thing.

Did I:

1. Fry the CPU by turning the PC on without thermal paste and heatsink?

2. Did something to the power supply when I cleaned it?

Do you think you can help me with this? Thank you so much for your time and your attention.

Best regards,
André

Processor - Intel® Pentium® III & Celeron® (66/100/133Mhz Front Side Bus) (FCPGA Type).
- 300/333/350/366/400/433/450/466/500/533/550/600/650/667/700MHz or above.


Chances are BIOS doesn't support your chip. The last listed speed is 700MHz. As new generations came forth, they operated at different voltages. To get the higher speeds, they went to a lower voltage on a smaller node (nm size) If the BIOS doesn't recognize the CPU, it might not be able to set the appropriate voltage and boot as expected.
 
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Solution

aqgon_6

Commendable
Mar 1, 2018
23
0
1,510
Processor - Intel® Pentium® III & Celeron® (66/100/133Mhz Front Side Bus) (FCPGA Type).
- 300/333/350/366/400/433/450/466/500/533/550/600/650/667/700MHz or above.


Chances are BIOS doesn't support your chip. The last listed speed is 700MHz. As new generations came forth, they operated at different voltages. To get the higher speeds, they went to a lower voltage on a smaller node (nm size) If the BIOS doesn't recognize the CPU, it might not be able to set the appropriate voltage and boot as expected.

Thank you for the fast reply, I reassembled everything and bought some cheaper made but more readily available thermal paste and retried with the original configuration Celeron 600 Mhz CPU. It booted with no problems, so as soon as I saw the line on the screen I shut it off. Did the same with the 866mhz P III right after with thermal paste also, and it went back to no image, so I guess that's that, "or above" might perhaps mean 800mhz as the limit?

Two more questions please:

1. As a beginner, what Pentium III processor would you recommend for me to look for this motherboard? Is a 500mhz Pentium III, for example, better than my 600mhz Celeron?

2. My front panel lights are still not turning on, I have doubts about the connections. I don't know if I can ask here or create a new thread but here it goes:

After inserting all the obvious pin cables on the board, I have two cables left with no written entry on the board:

- "Turbo LED" 2 pins cable, with no apparent input on the board, white and yellow wires;

- and the "Power LED" 3 pins cable, which entry is only of 2 pins on the board, white and green wires.

Other board free pin entries:

- "EXTSMI" - 2 pins

- KEY LOCK - 5 pins

- INFRARED - 4 pins

How should I connect the remaining two cables?

Thank you so much for all your help.
 
the front panel LEDs are polarized - so you probably have to reverse the ones that are out. the motherboard should have the silkscreen for the connectors either + or -

btw the two should be fairly close in performance the PIII is lower clocked but has more L2 cache

Thank you for the fast reply, I reassembled everything and bought some cheaper made but more readily available thermal paste and retried with the original configuration Celeron 600 Mhz CPU. It booted with no problems, so as soon as I saw the line on the screen I shut it off. Did the same with the 866mhz P III right after with thermal paste also, and it went back to no image, so I guess that's that, "or above" might perhaps mean 800mhz as the limit?

Two more questions please:

1. As a beginner, what Pentium III processor would you recommend for me to look for this motherboard? Is a 500mhz Pentium III, for example, better than my 600mhz Celeron?

2. My front panel lights are still not turning on, I have doubts about the connections. I don't know if I can ask here or create a new thread but here it goes:

After inserting all the obvious pin cables on the board, I have two cables left with no written entry on the board:

- "Turbo LED" 2 pins cable, with no apparent input on the board, white and yellow wires;

- and the "Power LED" 3 pins cable, which entry is only of 2 pins on the board, white and green wires.

Other board free pin entries:

- "EXTSMI" - 2 pins

- KEY LOCK - 5 pins

- INFRARED - 4 pins

How should I connect the remaining two cables?

Thank you so much for all your help.
 
  • Like
Reactions: RodroX

aqgon_6

Commendable
Mar 1, 2018
23
0
1,510
the front panel LEDs are polarized - so you probably have to reverse the ones that are out. the motherboard should have the silkscreen for the connectors either + or -

btw the two should be fairly close in performance the PIII is lower clocked but has more L2 cache

Thank you for your help, I got the lights working!

As for the CPU I guess I'll wait for the heatsink and cooler to arrive before I find another one, maybe a 800mhz Pentium III, I really hope it gets recognised by the board. I'm kind of unsure now due to the limit. All I wanted was to find the best possible Pentium III processor within the socket 370 line to replace this 600mhz Celeron. I thought it would be a simple switch but I guess my newbieness made it all unravel.

The thing that is really unpractical is that in any case I have to install all of it - heatsink, cooler, thermal paste - with any new CPU as if it was a definitive install, just to even check that it is working. Given the torture I apparently submitted these two CPUs - more our less 5 seconds each time without paste or cooler to check if it booted and recognised the CPU - I guess I shouldn't take the risk anymore.