PS2 backups without chip?

[Kumar]

Hi, I know this is going to sound like a stupid question but I was wondering if there is anyway to play my backups of playstation 2 games on a PS2 without it being chipped? Maybe using the Action Replay 2 or Gameshark?
I am guessing the short answer is no but am hoping there is a way!
Many thanks to all who take the time to reply.
Kumar

[Warlock]

Version's 1,2 and 3 can play backups using a gameshark and the cog,knife method. I have never tried this i always install a chip but i am told this works. ##### out www.ps2ownz.com for a description of the cog-knife method