Member Avatar for xxxgaryxxx

Hi, firstly, I'm a doughnut:) my vaio FR415B was working fine apart from a noisy fan so I decided to clean the heat sink vents.. on taking the machine apart I found them to be completely blocked with fluff.. great, found the problem.

Have cleaning and refitting everything, I now get a dead lappy.. the green power led illuminates, the HDD led lights momentarily and the floop drive tries to start.. this all happens within a second of pressing power on and then the lappy dies.. There's no audible or visual error codes.

I've taken out the CPU again complete with fan assembly and found that I bent one of the pins on refitting.. what a *&^%:$ I've straighted it again and resoldered the pin as it seemed loose (I have a heat control soldering station with very fine tip).

still no joy, the symptoms are exactly the same.. furthermore, removing the CPU and fan assembly again and ttrying the power on with it removed gives just about the same symptoms with the only exception is the power light, hdd light and floppy trying to start takes a little less time than.

the pin that was bent was touching an adjacent pin.. do you think I've shorted the cpu to the extent it's now knackered? it's a celeron 2.8ghz jobby.

hope you can help, if nothing else, to give me some diagnostics tips to check out the cpu an other components... would be wondeful if you could hel fix it for me though.... unfortunately, I don't have another machine to try swapping parts over from.

cheers Gary

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  • Latest Post Latest Post by bobbyraw

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A compact, practical supplement to the thread. Both and rightly warned that repairs around CPU pins are high risk. The checklist below gives a safe, ordered set of tests to narrow whether the fault is the CPU/socket or the surrounding power circuitry, and what to try before buying parts or doing more solder work.

  • Power-discharge first: remove main battery and AC, then hold the power button ~30 seconds to drain capacitors. Try powering with AC only (or battery only) to isolate adapter/battery issues.
  • Minimal POST: remove nonessential devices (HDD, optical, wireless cards) and try to boot with a single RAM module in the primary slot. Swap modules and slots if available.
  • Visual cleanup and inspection: under magnification look for solder bridges, flux residue, lifted pads or scorch marks around the CPU/socket and nearby VRM components. Clean flux and debris with high-purity isopropyl alcohol and a soft brush.
  • Multimeter checks (low-risk): with the board powered briefly, measure the DC jack input and the main regulator outputs (3.3V, 5V and the CPU core rails). If rails are absent, the power stage is the likely culprit. With power removed, check continuity from power rails to ground; a near-zero short indicates a shorted pin, solder bridge, or damaged component.
  • Check board fuses and MOSFETs: a blown SMD fuse or shorted MOSFET near the input/VRM will cause instant shutdown and is often replaceable without replacing the whole board.
  • Avoid amateur soldering of CPU pins: soldering pins risks lifting pads and creating hidden shorts. If solder was applied, desolder excess with wick and a low-heat iron or seek a micro-soldering service.

When socket pads are lifted or multiple rails short to ground, replacing the motherboard or sourcing a donor board is often the most practical route. These tests follow the cautionary points raised by and and are intended to limit further harm while identifying the defective subsystem.

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Member Avatar for mechbas

No joy is about the size of it and this isn't going to make you any happier.
CPUs are rather delicately made. Odds of your getting the pin back in the right place aren't exactly in your favor. Delicately put, the CPU is beyond the end of it's rope.

Member Avatar for bobbyraw

yow bro, where in the world did you get the idea to solder a pin on a cpu, i suggest you start looking for a new CPU for the Lappy LOL

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