Putting it all together:
The short answer is that every PC is perfect if it’s constructed for you! My advice is if you need a very fast PC, pick a PC with a good CPU and RAM, maybe for CPU an Intel i5 or i7, and for RAM, at least bigger than 4 GB. In addition, if you have the budget I would advise to pick SSD, because they are substantially faster, but only if you don’t need a lot of storage space.
If what you really need is Storage, invest in HDD, even though it is slower, you will find the best price for bigger storage amounts. However, if you’re into photography, it’s a must to have the best Graphics Card possible, maybe an NVIDIA GTX.
Lastly, if you’re a gamer, you will need the best of the above, because games nowadays require a lot from you’re PC.
Now you have the capability to choose the perfect PC for you, so go out there and find the Computer of your dreams. Just remember one thing:
It’s hardware that makes a machine fast. It’s software that makes a fast machine slow.
This meaning that a good managing of your PC is one of the best solutions for a perfect PC.