Chosen Solution

I need urgent help!, my macbook pro (mid 2009), just start to slow down, but severaly, i can`t even start an app. I even erase the HD and reinstall snow leopard, but its still the same and i try to diagnose with pressing D at power on with Installation disc but , dont enter diagnostic mode or something, i hope can someone help me :( thankyou.

How well does it run when booted from the installation DVD? I would reformat the hard drive using the “write zeros” option, to eliminate any bad blocks, give it one partition, then install a new system.

Is it not possible to fix it without erasing the hard-drive?

My Mac is very slow after awhile. Then I restart and it gets better, but often after a while it goes back to be slow and then eventually also “hangs”/freeze… Mats