While I have seen guys use as much as 2000 mgs of test per week, and they are still alive, it is highly undesirable to use such humongous dosages of steroids. First of all - if you can't benefit from like 500-750 mgs of test - there is something wrong with you. Be it genetics, diet, or training - there is definitely something wrong, as this mind of dosages will greatly increase your test levels far beyond the natural limits. Also, a good way of keeping the steroid dosages low is proper stacking. Sometimes 300 mgs of one steroid coupled with 300 mgs of another (600 total) will give much better results than 800 mgs of one single steroid, and yet will cause much less side effects. Yeah, the side effects also play a huge role. Beginning from a certain dosage, you stop getting additional benefits, and start getting more side effects instead. Therefore, one can take huge amounts of steroids, but that does not mean that these dosages will lead them to huge gains, as bodybuilding is much more than just juice.