Electronic – CPU considerations for PCB software (routing) when purchasing a new computer

Fundamentally, it basically boils down to the fact that the software is way easier to design with only 45° angles.

Modern autorouters are getting better, but most of the PCB tools available have roots that go back to the DOS days, and therefore there is an enormous amount of legacy pressure to not completely redesign the PCB layout interface.

Furthermore, many modern EDA packages let you "push" groups of traces, with the autorouter stepping in to allow one trace to force other traces to move, even during manual routing. This is also much harder to implement when you aren't confined to rigid 45­° angles.

Is there a web site that can be fed with the circuit and it would route it and would give me the final bitmap of the PCB?

Querying Google for "PCB Design Service" yields lots of offers, but obviously, you don't just feed them with the circuit but also with (probably a lot of) money. PCB design cannot be fully automated and will be done by humans.

I'll be also glad if you guys point me out to some free software for such PCB routing.

I can recommend KiCad. This software can also work together with online autorouters (which is what you might be looking for) such as http://www.freerouting.net/, but beware that this no "circuit in, PCB out" magic machine. Unless you have a really high number of signals, the effort usesd in correctly configuring the autorouter to produce an acceptable result is much higher than routing by hand. Also you still have to place the parts, which is sometimes the hardest part.