You did everything right. Turned the laptop over, read the model off the sticker, found a part that says it fits, ordered it. It arrives and it doesn't fit.
We see this a lot, and it's hardly ever the customer's fault. Manufacturers reuse model names, sell the same laptop in a handful of different builds, and sometimes change parts halfway through a production run. The name on the sticker gets you close. The part number is what gets you the right part.
Here are a few real ones that came across our desk recently.
Two laptops, one name
Someone asked us for a screen back cover for a Dell Latitude 3550. Easy enough, except Dell has sold two completely different laptops with that name.
The first one came out around 2015. The second is a 2024 model. Apart from the name they have nothing in common. The back cover for the newer one is Dell part H5WD3, which it shares with the Latitude 3540. The old 3550 takes different covers altogether.
Search "Latitude 3550 back cover" and you'll get both, often on the same page, with nothing to tell you which is which. If all you have is the model name, it's basically a coin flip.
The Dell service tag clears it up straight away. It tells us exactly which machine it is and what it left the factory with.
Same model, different build
This one is even more common. One model gets sold in several configurations, and some parts change depending on the build.
The Lenovo ThinkBook 15-IML is a good example. Some units have Intel's built-in graphics and some have a separate graphics card, and the heatsink (the metal cooling plate that sits over the processor) is different for each:
- 5H40S19991 for the built-in graphics version
- 5H40S19995 for the version with a separate graphics card
In photos they look almost the same. Fit the wrong one and it either won't line up with the chips on the board, or the graphics chip ends up with no cooling at all.
Keyboards on the same laptop are just as bad. That ThinkBook palmrest comes with or without a backlight, with or without a fingerprint reader, in different colours and layouts, and every combination has its own part number.
Same family, newer generation
Manufacturers love keeping a family name and adding a "G2" or "G3" on the end. The parts often change completely between generations.
The ThinkBook 15-IML and the ThinkBook 15 G2 sound like close relatives. They're not. A hinge set sold as 5H50S28995 shows up every time you search for ThinkBook 15 hinges, but it's for the G2, G3 and G4, which have a redesigned chassis. It won't fit the 15-IML.
HP does it too. A ProBook 450 G6 and a 450 G8 share a name and a screen size, but you can't assume the parts swap over. We regularly get people telling us they have a G8 when the label says G6, and the battery they were about to buy would have been wrong.
Be careful with marketplace "fits" lists
Use them as a starting point, not as proof.
A lot of listings on the big marketplaces copy their compatibility lists off each other. Some are too broad and list models the part doesn't fit. Others leave out models it does fit. We've seen batteries listed for the wrong laptop just because two part numbers were one character apart, with completely different voltages.
The manufacturer's part number, checked against the machine itself, is the only check we trust.
What we ask you for, and why
When you ask us for a part, this is what we're after, roughly in this order:
- The part number on the old part. Most laptop parts have a sticker or a stamped code, and it's the best information there is.
- The serial number or service tag. Lenovo, Dell and HP all let us look up what a specific machine shipped with.
- The full model number, not just the family. "ThinkBook 15" is a family. "ThinkBook 15-IML 20RW" is a machine.
- Photos, if all else fails. A photo of the old part, or of the connector, sorts out most questions.
If something doesn't add up, we'll tell you before you pay, not after the courier has been and gone.
It might feel like a lot of questions for one part. But a wrong part costs you more than the part itself: courier both ways, a laptop sitting in pieces for a week, and sometimes damage from forcing something that almost fits. Ten minutes checking a part number is a much better deal.
Quick answers
Is my model number enough to order a part?
Often, but not always. Some laptops share a name across completely different generations, and many models come in several builds that use different parts. The part number on the old part, or the serial number or service tag, is more reliable.
Why are there two different parts for the same model?
Because one model is sold in different builds, for example with or without a separate graphics card, or with different keyboards and screens. Heatsinks, keyboards and screens often change with the build.
What should I send to get the right part?
The part number off the old part if you can see it, the serial number or service tag, and the full model number. A photo of the old part helps too.
Not sure which version you've got? Send us the serial number or service tag and we'll confirm the exact part before you order.