While you can piecemeal a PC together by purchasing components as you can afford them, but you don't really want to on the off chance you get a faulty component. You only have so long to return an item to the seller for a replacement, if it's faulty.
For instance, let's say you purchase the motherboard now and it's faulty. You won't know that until you have all the other components purchased some months from now. Rather than sending the motherboard back to the seller for a quick replacement, it will have to go to the manufacturer for an attempted repair and only if that fails, a replacement. This process often takes several weeks.
Best practice is to save your money until you can purchase the entire system.
Everything is compatible. An SSD is a luxury, not a necessity. If you can afford one, it's great. If not, you can always add it later if you feel like it.
Btw, there is one downside of buying things part by part. If you have a lemon, you do not know it immediately. And after sometime, you can not return to the vendor, you have to go through the RMA process. So if you have some ways to test the parts (lets say a friends machine) after you get them, it will be great .
Everything is compatible. An SSD is a luxury, not a necessity. If you can afford one, it's great. If not, you can always add it later if you feel like it.
Btw, there is one downside of buying things part by part. If you have a lemon, you do not know it immediately. And after sometime, you can not return to the vendor, you have to go through the RMA process. So if you have some ways to test the parts (lets say a friends machine) after you get them, it will be great .
Just to clarify, an SSD is indeed an optional luxury for those that can afford one, but the advantages of an SSD over a hard drive are:
1) No moving parts so the SSD can't be damaged by excess vibration or accidental impact such as when it's dropped (within reason of course).
2) (and this is the main reason why people buy them): They perform much faster than a hard drive. This means that boot times are much faster, Windows loads in seconds, and so do applications or games which are installed on it.
The downside to buying an SDD, however, is that capacity-wise they are much more expensive than a conventional HDD at this present time, though prices are falling and will continue to fall as more people buy them.