I've herein attached a configuration of a PC for deep learning. Please see this one and ask me whether this configuration is perfect or not regarding the deep learning phenomena.
A cheap computer, may result with lesser features. For deep learning you need to access information and your computer should allow you use it at higher speed. And cheap computers might be slower.
I recommend that you think of buying smart phone, because it will allow you carry it where ever you go, and you can use it anytime. Further, you can use it as phone, video and audio device. Consult this article 'El-Hussein, M.O.M. and Cronje, J.C., 2010. Defining mobile learning in the higher education landscape. Journal of Educational Technology & Society, 13(3), p.12.'