Member Avatar for baltimoreharps

I just assembled a D620 from spare parts. The LCD, MB, CPU, DIMMS and heatsink are new. The rest of the components are from other system repairs.

On power up, the system LEDs light up as normal then after about 5 seconds, it shuts down. We never get to the Dell splash screen. My first guess would be the processor but this is new and Im temporarily holding off on that. My first practical guess may be the fan or modem as Latitudes tend not to even post if there is a problem with one of these 2 parts (these parts are suspect as they have been sitting around for a while and I cant remember whether they were working when I got them or not).

Any other suggestions on what to swap out first?

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  • Latest Post Latest Post by jbennet

Dani AI

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This thread, with contributions from and , is a good example of an intermittent "no POST / early shutdown" problem on a Latitude D620 assembled from spare parts. The symptom often comes from power-delivery or mechanical contact problems rather than immediately-broken CPUs. Below is a concise, practical troubleshooting flow and a few hands-on checks to isolate the fault reliably.

  • Start with the basics: verify the AC adapter and battery behavior (try AC-only and battery-only boots), and perform an EC power drain (remove power, remove battery, hold the power button 15–30s).
  • Reduce the system to a known-minimal state: one good RAM module in the primary slot, no HDD/optical, no cards (WiFi/modem), internal cables re-seated. Try swapping the single RAM stick between slots and test another known-good stick if available.
  • Inspect the board visually for loose standoffs, stripped screws, bent pins, bulging/leaking caps, or solder cracks. Check the DC jack and power-button/cable seating. Look for any foreign metal or misaligned screws that could short the PCB.
  • Use built-in diagnostics (boot menu, F12 on many Dells) or memtest86 to catch memory and basic-board faults. If the system posts sometimes but not always, try thermal/stress cycles to reproduce the failure.

Thermal/mechanical best practices (helps prevent intermittent contact): clean mating surfaces with high‑purity isopropyl alcohol, use a proper CPU thermal compound, align the heatsink before making contact, and tighten retention screws gradually and evenly in an X/star sequence so the sink seats flat. Make sure the fan header is connected and the fan spins freely. Avoid over-tightening retention hardware.

If the fault survives these steps, work methodically from inexpensive to expensive replacements: adapter/battery, RAM, drives/cards, fan/thermal assembly, then mainboard/CPU last. Keep an action log of steps tried and any diagnostic codes seen; that record speeds troubleshooting and avoids needless part swapping.

Member Avatar for baltimoreharps

I do realize, though, that even though the MB and CPU are new, they could still be dead. I'm playing the numbers right now on that in all probability they are not the problem. I will test the CPU Monday at work on another machine.

Member Avatar for baltimoreharps

Well, its fixed. I went back and opened it up, looked everything over to make sure everything was connected properly. When I booted, it fired right up. I got the OS installed, no problem. After a while, when I was rebooting, it did the same thing again. I opened it and all I did was open and retighten the processor screw and she fired right up with no problems since.

Member Avatar for jbennet

yeah she was probably overheating if the heatsink wasnt properley contacting the CPU

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