AC Adapter? 65W or 90W?

[Olwe]

My T430 came with a 65W/20V adapter, but I've seen 90W/20V for it also? Which do I need? What's the difference?

[rkawakami]

First off, what's the 7 character model type of your T430? It should be on a black and white bar code label on the bottom of the system and is also on the main BIOS page. If purchased from the factory, it would have come with the "proper" adapter. If bought off eBay, Craigslist, or from a garage sale, then you might have an improper adapter.

Generally the 65W adapters are specified with systems that have integrated graphics (i.e., Intel graphics processor that uses a portion of the system memory). 90W adapters are for those systems that have a discrete graphics chip (i.e, ATI, NVidia, etc.) as they have their own memory and higher power requirements. You can safely use a 90W adapter with the integrated graphics system but it's not recommended to run a discrete system with the lower power (65W) adapter. It can force the system into running slower and/or affect the charging rate of the battery.

My recommendation is if given a choice between the adapters and the price is the same or nearly so, go for the 90W. It will work for your current system and could be used if you upgrade to a system that has the higher power requirement.