I wasnt going to reply because i know you are not going to believe it then i thought lets give a final try.
Source: 'To me Candragupta was a man of the Uttarapatha or Gandhara if not exactly of Taksashila' (Indian Culture, vol. X, p. 34, B. M. Barua).
Source: Invasion of India by Alexander the great, p. 405. Plutarch attests that Androcottos had seen Alexander when he (Androcottos) was a lad and afterwards he used to declare that Alexander might easily have conquered the whole country (India); Was Chandragupta Maurya a Punjabi? Article in Punjab History Conference, Second Session, Oct 28-30, 1966, Punjabi University Patiala, p 32-35
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Source: Appian (XI, 55). Some historians state that he belonged to Kunar and Swat valleys. See: The Kambojas Through the Ages, 2005, pp 150-51, Kirpal Singh. This reference also seems to indicate that Chandragupta belonged to north-west rather than East India.
Source Arrian. iv, 30. 4
Source: Invasion of Alexander, 2nd Ed, p 112, Dr J. W. McCrindle; Op cit., p 33, Dr H. R. Gupta; Dr McCrindle further writes that modern Afghanistan was the ancient Kamboja and that the name Afghanistan is evidently derived from the Ashvakas or Assakenois of Arrian See: Megasthenes and Arrian, p 180; Alexander's Invasion of India, p 38; Dr J. C. Vidyalankar identifies Sisicottos as a Kamboja ruler: See Itihaas Parvesh, pp 133-34, Dr J. C. Vidyalankar; Kamboj Itihaas, 1973, p 58-59, H. S. Thind.
Source : Op. cit., pp 32-35, Dr H. C. Gupta; Also: The Kambojas Through the Ages, 2005, pp 149-154.
Tribune writes: "Most historians are of the view that Chandragupta Maurya belonged to Bihar, and that he called himself Maurya because his mother was the keeper of royal peacocks (mor) at Pataliputra. He came to Punjab and conquered it. Afterwards, with the help of the Punjab army he seized the Nanda empire. However, there are reasons to believe that Chandragupta belonged to the Kshatriya caste of the ruling Ashvaka tribe of the Koh-i-Mor territory. He called himself Maurya after his homeland" (Ref: Article in Sunday Tribune, January 10, 1999 They taught lessons to kings, Gur Rattan Pal Singh; Also cf: Was Chandragupta Maurya a Punjabi?, Punjab History Conference, Second Session, Oct 28-30, 1966, Punjabi University Patiala, p 33, Dr H. R. Gupta)
It is notable that Adiparva of Mahabharata (verses 1/67/13-14) also seem to connect Maurya Ashoka with the Ashvakas
Source: yastvashva iti vikhyAtaH shrImAnAsInmahAsuraH |. Ashoko nAma rAjAsInmahAvIryaparAkramaH. ||14|| tasmAdavarajo yastu rAjannashvapatiH smR^itaH |. daiteyaH so.abhavadrAjA hArdikyo manujarShabhaH ||15.|| ( See English Translation): "That great Asura who was known as Aswa became on earth the monarch Asoka of exceeding energy and invincible in battle."
Source: op cit., (Part II), p.416-17, Dr D. B. Spooner Thus, Dr Spooner's comments also point to the north-western origin of the Mauryas.
It is however interesting to see that the scholars also identify the Ashvakas as a branch of the Kambojas. They were so-called since they were specialised in horse-profession and their services as cavalrymen were frequently requisitioned in ancient wars. V. R. Ramachandra Dikshitar writes: "Both the Puranas and the epics agree that the horses of the Sindhu and Kamboja regions were of the finest breed, and that the services of the Kambojas as cavalry troopers were requisitioned in ancient wars
Source: War in Ancient India‎, 1944, p 178, V. R. Ramachandra Dikshitar - Military art and science.