Searching for a second power adapter for my M4700, I found on the DELL store a 180w model and a 130w model, both claiming to be compatible with the M4700.
Since the computer came with a 180w PSU, would a 130w somehow cripple the machine performance ?
This is important as I do video editing requiring full CPU and I/O performance.
NB: I tried to use a 120w "universal" power supply (which I purchased for a previous computer): while the M4700 "worked" with it, it complained about not recognizing the PSU (I can agree with that), and did not recharge the battery (I can live with that), but most of all, CPU speed AND disk I/O was crippled to an unacceptable level, making my video editing software unusable. (this is a bit odd, as 120w is more than what the M4700 is consuming (even at 100% CPU, but without tons of power-hungry devices connected).
Can I buy the DELL 130w PSU in confidence ?
No. If the system came with a 180W adapter, that's what you need. Don't replace it with a lower-wattage power supply - doing so will shorten the life of the adapter, and cause the system to run at less than full speed.