Fuse size for kettle lead

I lost all power to my desktop. Tried a different kettle lead, and still dead. So I tried a different motherboard and a different power supply. It was still dead.

Finally found out I had 2 duff power leads that the fuse had gone in(the spare must have gone in last few years and I never noticed). Anyway, I checked the fuse in one of the leads and it's a 5 amp fuse.

This seems a bit small for a desktop PC (especially as I have an 800 watt enermax PSU). Is the fuse for a power supply supposed to be this small?

I just want to make sure I fit the right fuse, as if it's supposed to be a 5a fuse, I don't want to fit a 13a fuse and risk the fuse not doing it's job. On the other hand, I don't want a fuse too small and have it blow to easily.

Any ideas?

power = current x potential difference ;)

A 5A fuse on a 240v mains circuit can handle 1200W throughput before it blows. More than enough :)

Yeah, 5amp is more than enough for a PC.

You could have had an electricity spike during some bad weather or during the night which has caused the fuse to blow.