Ok I bought a second hand Toshiba Portege r830- 138 a year ago and it didn't come with a recovery disk..
Since my laptop is beginning to run slow I've been trying to reformat/reset back to factory settings..
[I've tried the hold down (0) key button and press the power button once at the same time and wait for the beep and then release the (0) key.. But it doesn't seem to work it just brings me right to the log in screen..
Then I've tried the press (F8 button) fast but it just brings me to Advance Boot Options... Which is useless cuz it doesn't bring me to the reset to factory settings..
So please tell me how I can reset to factory settings without a recovery disk because my brother totally did it back then without any disks I just forgot to ask him how to do it.. And now I've lost contact of him so I can't ask him..

Thanks in Advance ✌