no beep no POST

[SCRIBUS]

I am trying to revive a Compaq Presario SR 1780 AN PC.

Everything was ok some weeks ago. I used it for several hours and had normal shut down late at night. Next morning I pressed start button, front led came on also all fans and hard drive but no beep and no POST just spinning discs and fans. Have tried new PSU, new MOBO plus tried with everything removed except PSU, MOBO and CPU. Still no beep or POST. Have not tried new CPU but even with CPU removed there should be beep and POST, I think.
Scribus

[chrishea]

If it won't Post it normally means some kind of hardware problem. You won't get beep codes. In this situation, it usually sits there for a while with the power on and then it restarts itself (and does this over and over until you kill it).

When you tried the bare-bones approach what memory sticks did you use? If they were the same as you used previously, then you need to check those out as well. If you swapped some others in then you need to be sure those are good. I presume that when you tried a different MOBO, it was known to be good and that it had it's own video card that was also known to work. If these aren't the problem then it could be your CPU. There is also a possibility that the CMOS battery might be a factor.

[thewebhostingdi]

Remove every component from your motherboard. CPU, Memory, Display card all just plain motherboard. Then give power supply to motherboard. Still if you can not hear any beep chances of motherboard dead. The other possibility in this situation is the beep speaker gone. If you can replace that it is good.

[SCRIBUS]

Remove every component from your motherboard. CPU, Memory, Display card all just plain motherboard. Then give power supply to motherboard. Still if you can not hear any beep chances of motherboard dead. The other possibility in this situation is the beep speaker gone. If you can replace that it is good.

Thank you for your suggestion. I have tried it and still no beep. I f I ever solve this one I will post result.

Scribus

[SCRIBUS]

If it won't Post it normally means some kind of hardware problem. You won't get beep codes. In this situation, it usually sits there for a while with the power on and then it restarts itself (and does this over and over until you kill it).

When you tried the bare-bones approach what memory sticks did you use? If they were the same as you used previously, then you need to check those out as well. If you swapped some others in then you need to be sure those are good. I presume that when you tried a different MOBO, it was known to be good and that it had it's own video card that was also known to work. If these aren't the problem then it could be your CPU. There is also a possibility that the CMOS battery might be a factor.

Thank you for suggestions. I have tried them but still no beep.

Scribus

[finito]

Hmm If you removed everything and tried it with only the motherboard and CPU, maybe the CPU is gone?

[hypersonic]

Hey.. can u please update me with the Front LED, is it blinking or it steady On? If its blinking.. its usually an issue with the POWER SUPPLY UNIT of the sys. But since u have already replaced the PSU, i would say try getting new memory for it, if it has two memory modules, try replacing both the memory modules. If this also, doesn't work,Sometimes it could be an issue with the LCD too, where u are not able to see anything on the screen.I would suggest connecting an external monitor and check if u can hear any sound when the sys starts. Some times when the issue is with the LCD, sys comes up, but u won't be able to see anything on the sys.So, try and see if u can hear the windows loading sound. If you have already tried external monitor and replacing memory, then i would suggest you to check the processor.