Legal
Stay connected
Compatibility tips and upgrade deals, straight to your inbox. No spam.
Your system
6 guaranteed-fit options
This option is out of stock.
Free tools from Seifelden — no purchase needed.
Checks the drivers on your HP ProBook 4421s, installs the safe updates Windows offers, guides the rest to the official download — and confirms exactly which of the upgrades above your machine has room for.
Specifications reported for the HP ProBook 4421s.
Good to know
We've already verified which memory and storage upgrades fit this exact machine — they're just not in stock at the moment. Leave your email and we'll tell you the moment any of them is available again. Guaranteed fit, no wrong parts.