As per the Dharmic philosophies of Hinduism and Buddhism, an atheist does not necessarily go to hell provided he adheres to virtuous conduct or behavior.
Precise adherence to virtuous conduct and behavior in itself can lead oneself to enlightenment.
The female enlightened master Rajini Menon is an example of one who attained enlightenment just through virtuous conduct ....
I have explained more on this
thread of mine...
http://www.spiritualforums.com/vb/sh...d.php?t=129341
Some sayings in this regard...
Wholesome virtuous behavior progressively leads to the foremost. - Buddha AN 10.1
If you do right, irrespective of what the other does, it will slow down the mind. - Rajini Menon
“When even one virtue becomes our nature, the mind becomes clean and tranquil. Then there is no need to practice meditation; we will automatically be meditating always.” - Swami Satchidananda