Valve rolled out a new update for Steam, in which the company noted that the Windows XP SP1 support will be dropped on August 31st. This obviously does not mean that Steam will stop working on Windows XP SP1 systems. However, the company will not provide any help or support when players face problems with it (at a later date). In addition, there is a possibility for a future update to break Steam on Windows XP SP1.
Of course, Windows XP SP2 and newer versions will be fully supported by Steam. In other words, this does not mean that Valve will drop the entire Windows XP support.
We really don’t know why a PC user would be stuck on Windows XP SP1 but if you’re one of them, know that you will need to upgrade eventually, especially if you’re using Valve’s distribution service.
Moreover, since Valve will drop SP1 support, we highly recommend avoiding using it as your credit cards might be in danger from a hacker attack. This is mere speculation but since there won’t be any SP1 support, you will be held entirely responsible for still using it on an unsupported OS. As they say, better be safe than sorry, right?