Playstation (PSone) mod chip question

OK I am having some issues (mostly mental) I have an older model playstation (big grey one) that uses a "mod pod" in the serial I/O and a friend of mine has a chipped PSone (you know the slim version)...ok with that aside, my friend has a pretty good collection of burnt PSX games and they all work on his chipped system, but on mine I maybe can get 2 or 3 to work so I am thinking its because his is chipped and mine isn't ok? so no big deal.I now also have a PSone that I got in a trade and I am wondering what would be the best chip to get for it and how difficult is it to install? (and yes I already asked what chip he as and he has no clue because he bought his modded)ok..*takes a deep breath and calms down*...there now thats all out, hopefully someone can help me out with some info so thanks in advance for the read and any help.

Perhaps Breaker Pro?

First determine which model you have by SCPH-XXXX, where XXXX is the model #Non modded way.. boot disc : Breaker Pro though it doesnt work on everything.Mod chips are the way to go, if you want to play anything.I use modchip 8-wire PSX Stealth IV Modchip, the common norm is 7 , 6, 5, 4 wire depending on your model # and your needs.soldering it yourself to make costs go down, and its fairly easy, most sites you buy it from, will show you the installation process, diagrams/tutorials etc.This is an old faq but maintains good info's on a starting point to understanding the evolutions of the mod chip era...http://modchip.aeug.org/faq.html im surprised it's still around.. after a decade.oh yea almost forgot this lil gem ... http://www.megagames.com/psx/psx_patches.shtml not needed in new mods, but handy for older type mod chips.