Member Avatar for bishop bahamas

hello everyone i own a dell demension desktop 3000 that would not turn on. i checked the power supply unit and it works fine in another machine and pass all testing but when i place it in the dell it would not turn the system on. Can anyone help me

  • 3 Contributors
  • 4 Replies
  • 94 Views
  • 1 Day Discussion Span
  • Latest Post Latest Post by caperjack

Dani AI

Generated

Practical steps to narrow this down for a Dimension 3000 — building on points from and . Work on a grounded surface, unplug the mains before touching components, and keep handling simple so parts are not damaged. The checks below go from safest/quickest to more technical.

  • Confirm the case power switch and wiring: unplug the front-panel power plug from the motherboard and briefly short the two power-on pins on the header with a screwdriver. If the system powers, the case switch or cable is the culprit.
  • Try a true minimal boot: remove hard drives, optical drives, and all add-in cards. Leave CPU, cooler, one RAM stick in the primary slot and video (if needed). Try each RAM stick alone and try other slots to rule out a bad module or slot.
  • Attach a system speaker (if not present) and listen for beep codes — they quickly indicate RAM/CPU/video class faults.
  • Inspect the motherboard visually for bulging or leaking electrolytic capacitors, scorch marks, or blown components. Physical damage like that often means the board needs replacement or capacitor repair.
  • If a multimeter is available: check that the PSU provides standby +5V on the purple pin with mains connected, and that the PS_ON (green) goes low when the board requests power. If the PSU runs when manually started but not when connected to the board, the motherboard is not signalling the PSU.
  • Use the paperclip/start-up test only to confirm the PSU outside the case and with caution; it does not prove the board will work when connected.

If the minimal-configuration test never powers the board while the PSU is known good, the motherboard is the likely failure. Match Dell board part numbers if seeking a replacement or consult a repair shop if capacitor replacement or board-level diagnosis is needed.

Recommended Answers

All 4 Replies

Member Avatar for caperjack

Does it turn on any lights on the motherboard ,should be red one somewhere on the board , usually when this happens its the motherboard gone bad

Member Avatar for bishop bahamas

yea a green light comes on on the motherboard. i think the motherboard is gone too! have a question thought does the same thing happen if the memory is bad.

Member Avatar for caperjack

yea a green light comes on on the motherboard. i think the motherboard is gone too! have a question thought does the same thing happen if the memory is bad.

green is good, yes ram could cause problems like this .

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.