His fight with Hashirama 90 years before the kyuubi attack.
( 90+16+??? <-- is 25-35) which is the age for when he fought Hashirama so he's 140-150 maybe.
i dont think he was that old because the third was like 70 and he knew the 1st and 2nd while they looked quite young probably late 20's early 30's so unless the 3rd was like 170 when he fought orochimaru chance's are he's more around the 90-115 mark
Over 80 years ago, when there were no Hidden villages, when the Senju Clan and the Uchiha Clan were slaughtering one another, Hashirama and Madara look so young (in their twenties I guess).