1st, my desktop (dell Dimension 5100) had been not used for several months. When turned on, the green error code lights 3, 4 and a flashing battery appeared, along with a beeping noise. I read up on the error code and assumed the power supply was the problem. I replaced the power supply with a new 1, now I get only a flashing orange power light. What is the problem, and can I transfer my old hard drive into a new desktop?

look here
DELL Dimension 9100 No Booting diagnostic light 1 green 2 3 4 green

Also bear this page and links in mnd

This may help you. This is Dell diagnostics, also light and beep codes:
http://support.dell.com/support/edocs/systems/dim5100/en/sm/tshoot1.htm#wp1122208

most likely a bad power supply or motherboard. Replace the power supply 1st

i have the same problem with my dell dimension 9600, it is the worst and most incompatable pc i have ever owned ,, lots of software issues
,driver issues , allways packing in half way through a game ,full of problems !i can safely say that it is going in the bin and i will never ever buy a piece of scrap DELL DESTRUCTION again , i dont know how dell have the nerve to sell such an unreliable piece of rubbish.

If there is no loss of functionality then I would say no.

When you mean the amber light, is that the blinking hard drive access light or the power light? Different cases have different colors on it. Mine has blue and green lights.

If you see the boot screen (bios) and then after it goes to boot, does it blink and hang?

This could be a simple operating system issue, hard drive or hardware/motherboard issue. If you could provide more information, that would help.

The green light just means it is plugged in and getting power.Try pulling the plug, the green light will go out. If you can remove the battery out of the motherboard, "it looks like a quarter", leaveit out for a couple minutes and out it in 'The same way it was" make sure you "look" at it before removing it, it has a little release thatenables it to lock in, or pop out. plug it in and give it a start. It may just be the settings got corrupted, that little battery saves the start settings, once it starts, we can go into the bios if any settings need changing, I'll keep an eye on this post, good luck

plz check the ram and powersupply unit and try to reset the bios

Hi

To help troubleshoot a problem, Dell Dimension 5100 has four diagnostic lights labeled "1," "2," "3," "4" on the front panel. When the computer starts normally, the lights flash. After the computer starts, all four lights lites solid green. The power button also lites solid green. If the computer malfunctions, the color and sequence of the diagnostic lights as well as the power button helps identifies the problem.

First, disconnect the power cord and remove all connections (Keyboard, Network, Mouse etc) as well as optional PCI Cards. Connect up the power cord (Monitor as well) and try powering the PC.
Check the diagnostic lights/system lights color and sequence and check the link below for more info (Assuming you have another system that can access internet)
Diagnostic Lights - http://support.dell.com/support/edocs/systems/dim5100/en/sm/tshoot1.htm#wp1120147
System Lights - http://support.dell.com/support/edocs/systems/dim5100/en/sm/tshoot1.htm#wp1114432

Reply with lights color and sequence as well as any beep codes and I will respond at best effort.

Mike

Hi

First disconnecting the power cord and re-seat all connections (Keyboard, Mouse espercially). Connect up the power cord and try powering the PC.

To help you troubleshoot a problem, Dell Dimension 5100 has four diagnostic lights labeled "1," "2," "3," and "4" on the front panel. When the computer starts normally, the lights flash. After the computer starts, all four lights display solid green. If the computer malfunctions, the color and sequence of the lights identify the problem.

If the computer failed to start up check the diagnostic lights color and sequence and Check the link below for more info (Assuming you have another system that can access internet)
http://support.dell.com/support/edocs/systems/dim5100/en/sm/tshoot1.htm#wp1120147

Alternatively, contact Dell Support with the diagnostic lights color and sequence to raise a service call if the system if under warranty.

Mike