But even if he doesn't cum inside you, you could still get HIV from his pre-cum. Whilst HIV isn't passed on every time, each new risk increases the chances. And men with HIV become more infectious when they have an STI because the amount of HIV in their body goes up. So, whether or not you have HIV, STIs increase the risks. Because you can have an STI without knowing, a check-up at a sexual health clinic will let you know for sure.
Some men have regular check-ups for STIs so that they can have any infection treated quickly.
Men who aren't infected have no HIV and so cannot have a viral load. The higher someone's viral load, the higher the chances of HIV being passed on during unprotected sex. Tests can give an idea of what the level is. Having an infection or being run-down can make it easier for HIV to be passed on. Whatever a man's viral load, there is still a risk of infection if he and a man without HIV fuck without a condom.