It depends on your definition of "refurbish" - usually this means to replace any broken parts and bring it back to "like new" condition.

If you mean "upgrade", then the story changes, as you'll be limited to what's upgradable in the laptop - CPU is usually not replaceable without changing the whole motherboard, though sometimes they are. RAM usually is upgradable, but you're stuck to whatever type of RAM it came with originally (DDR2/DDR3/1866mhz etc). Hard drive can often be upgraded or swapped to SSD, but if the laptop is old enough to still use PATA that'll likely exclude any available SSD's. And even after upgrading, you're still stuck with old technology.

Re-purposing as mentioned above is probably the best course. Use it as a workshop computer, or something like that.

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