The 18.5V 3.5A (65W) charger with a yellow pin (technically a 4.8mm x 1.7mm connector) was a standard for many HP and Compaq laptops.
Compatible Laptop Brands & Models
This adapter is most commonly associated with older business and consumer laptops from these series:
HP EliteBook & ProBook:
EliteBook: 2530p, 2540p, 2560p, 2730p, 6930p, 8440p, 8530w.
ProBook: 4310s, 4410s, 4510s, 4520s, 4530s, 4710s, 6450b, 6550b.
HP Pavilion:
Series: DV3, DV4, DV5, DV6, DV7.
Models: G4, G6, G7, G42, G50, G60, G61, G62, G70.
Compaq Presario:
Series: CQ32, CQ40, CQ42, CQ45, CQ50, CQ56, CQ57, CQ58, CQ60, CQ61, CQ62, CQ70.
Compaq Presario Series (Yellow Pin)Since HP owned Compaq during this era, many Presario models used the exact same yellow-pin 18.5V 65W adapter:Presario V-Series: Models like V2000, V3000, V4000, V5000, and V6000.Presario C-Series: Many C300, C500, and C700 variations.Presario M-Series: Older models such as the M2000 and M700
HP Compaq Business Notebooks:
Models: 500, 510, 530, 620, 625, 6710b, 6720s, 6730b, 6735s, 6830s, nc6400, nx6310, nx6325, nx7400.