Hard reset?

[Tybo]

Well I have 3gs 3.1.3 jailbroken and I have the white screen of death where you can hear everything like unlocking it but the screen is just white so I looked on youtude and one dude said just do a hard reset so I looked at comments alot of people says it work but if I hard reset will I have to restore because I don't have a computer but my 4.0 shsh are on file and how do hard reset

 

[pixelated]

Hard reset doesn't force a restore.
Hold down the Home and Sleep/wake buttons untill the phone turns off and restarts (ignoring the slide to power off dialogue that appears).