Computer lags, what could be the problem?

Question

Iron

Guys what the hell could it be..?
A few years ago I bought a PC, as a result, the games immediately lag (according to the requirements for the maximum, it should fly as a result for the minimum problems) in jerks for 10 seconds. every minute .. two sometimes every 5,
athlone 64x2 2.6Hz.
3GB nvidia 8600gt
512mb ram.
vidyuhu changed and hard changed the problem is not in them, the temperature is also normal.

Answer 1

"jerks for 10 seconds every minute" - check the capacitors on the motherboard for "bloating" - a common problem with such symptoms.

Answer 2

two sometimes in 5

You would announce what you launched and what lags, at what settings. So far, I see that you have:
1) a weak percentage, very weak by modern standards.
2) there is not enough RAM, now it makes no sense to install less than 4 gigs at all. For modern games, 8 is generally better.
3) an old video card, although you can live with it (you yourself have one)
It is also possible that the problem is in old drivers.