Repairing an Acer E5-521 Laptop: A Case Study

Opening The Patient Up For Diagnosis

A handful of screws, some prying, and a few ribbon cable disconnections later, the keyboard and trackpad lift off from the chassis, exposing the motherboard and other internal components.

My worries about hinge damage affecting the motherboard turned out to be completely unfounded; the circuit board comes nowhere close to either corner. There's no risk of a broken DC-in jack board connection either as it is connected to the board using jumper wires, a necessity given its location in the opposite chassis corner from the mainboard. Another consequence of the board being so small is that it does not reach the battery bay either, and an additional bridge board running vertically near the middle is used to make the connection.

I wasn’t expecting the insides to look practically factory-clean from how rough the fall repairs looked. Then again, it is entirely possible that whoever put it back together after surgery gave it a good clean along the way.

The laptop’s layout is typical of contemporary models using processors with integrated graphics: the motherboard occupies the front-left corner, heat pipes carry waste heat from the CPU to the left edge’s fin stack where a thin blower fan shoves air through it and out the left side. Along the right edge, starting from the front, we find the laptop’s 1TB Western Digital disk drive buried under the right-hand USB ports’ ribbon cable, the unpopulated optical drive bay, and the DC-in jack. Most of the internal chassis surface has been copper-coated to mitigate electromagnetic interference, except for the optical bay area where the copper appears to also have been plated with tin, zinc, or nickel.

Acer may be reusing the same USB board across different laptop models. Instead of maintaining inventory of the same board with different model-specific flat-flex cables (FFC) attached, it picked a one-size-fits-all approach where excess length is simply tucked into the space behind the storage device, or wherever else may be convenient in other models.

Image 1 of 2

From the top, the only sign of damage I found, structural or otherwise, was a suspiciously large hole with a rough edge in the battery latch mechanism area. After sifting through the fallen bits and pieces, I found a broken screw well and its corresponding hole on the keyboard’s back. This failure pattern leaves me scratching my head: if something had fallen on the keyboard, I would have expected the support to get punched through out of the case. Here though, the break is on the inside, as if someone tried to rip the keyboard off. Did the first repair person forget to remove this screw before attempting to pry the keyboard off? The only other way I can imagine causing this type of failure would be repeated stress on either side of the support but such material fatigue would involve some seriously heavy keyboard pounding.

With the tour of general layout and obvious physical damage taken care of, let’s have our first serious look at the motherboard.

On the top side of the board, we find the power management circuitry responsible for handling external and battery power, the CPU’s core voltage regulator, a handful of additional voltage regulators responsible for generating the support rails (memory voltage and 5V/12V for the SATA and optical drives), the CPU hidden under its heat pipe mount, two DIMM slots, and the real-time clock backup battery.

With so few major components on the board, there isn’t a whole lot to troubleshoot before entering lost cause territory. Since we appear to have no power whatsoever, a logical starting point would be capacitors across the system (battery/external) power rail if we can find an obvious suspect to begin probing from. We know the external adapter provides 19V, so we’re looking for a capacitor rated for 25V or higher if we are lucky enough to have one in metal can format with markings on it (instead of multi-layer chip capacitor, which typically have no markings whatsoever).

MORE: Best Gaming Laptops

MORE: Gaming Laptop Previews

MORE: All Laptop Content