PC hardware forum: computer become hang quite often.(Hard disk problem)

If what you call 'complete format' is a system recovery back to factory conditions (not really clear) your laptop should be as fast as it was when it was new. But I assume you did a lot more than just that (such as installing photoshop, dreamweaver etc).

Did they tell you why they think it's the hard disk? It doesn't seem very likely.

If it works in Safe Mode and not in normal mode, it could be a problem caused by programs/services/malware. A new system recovery back to factory conditions is the solution then. But it could also be an issue of your graphic card; in Safe Mode runs in a very basic way, in normal mode all of it is used.

Any other hardware issue (motherboard or RAM) can lead to hangs also. The only way the hard disk could be the problem is that, for some reason, it doesn't run in DMA mode any more, but in PIO mode. That's easy to check. Then a new disk might be the solution.

The only way to find the cause is by elimination, and even that doesn't always work.

Kees