The most important part of selecting a mod-chip is to ensure that you select a "stable" chip, that goes into a "sleep mode" after booting the required game and can "wake up" again if needed to.
 
 
     
    STABILITY:
  There are many different ways to check if a mod-chip is stable, but unfortunately the most effective way is through experience. Things that you can check for yourself;
When you look at a mod-chip's PC Board you will note that among the few components there is a large I.C. or chip (sometimes more). When you read the markings on such a chip you will see that it will have part numbers (ignore these) and a large logo like name, this is what you should be looking at. Actel, Xilinx and Quicklogic have proven to be the best. The reason for this is; They are very well engineered chips with stability in mind. They have an "over voltage" protection feature, meaning that it will block voltage spikes which can damage the laser. The exact opposite of these 3 chips is the "Scenix or UbiCom" I.C. this is actually not the same type of chip as the Actel, Xilinx and Quicklogic chips. You can almost call it the big brother of the PSOne chip. It does not have any voltage protection and it's maximum clock speed is equal to the minimum clock speed required by the PS2. What this means is that laser damage can occur through a voltage spike, and data transfer is normally not very accurate.
Please keep in mind that the above mentioned is a more or less guide and by no means a rule.
     
 
 
 
 
     
 
 
 
 
     
 
 
  SLEEP MODE:
  After the chip has booted the title required, it will go into hiding and only monitor what the PS2 is doing. The advantage of this is that the chip does not interfere with the normal operation of the PS2 and it does not damage the laser by sending unnecessary signals it. Unfortunately since "sleep mode" is part of the code that is programmed on the chip, there is no way of checking for this feature on the actual chip.
     
 
 
 
   
      WAKE UP:
  Only chips that have a sleep mode can have a "wake-up" mode. Consoles from v7 (SCP39004) had a new feature added to them. The console can try and authenticate the disk that is being played at any time. People with v7 consoles, Magic 3 chips, and a NTSC or pirated version of Splinter Cell will know what I'm talking about. While playing the game it will go to a red screen that says "PLEASE INSERT A PLAYSTATION® OR PLAYSTATION® 2 FORMAT DISK" .If you have a chip installed with a "wake-up" feature the chip will wake up and resend the required data to stop this from happening.
 
   
     
     
     
      Now that you more or less know how to tell a good quality chip from a bad one it's time to ask yourself what your needs are. I will explain all the different features in detail.
     
       
      BOOTS PSone GAMES:
      I think you can figure this one out for yourself. (No matter what chip you have, you will never get100% of all PSone game to work on a PS2)
     
       
      PERFORMS SCREEN CENTERING / FIX FOR PSone GAMES:
      When a NTSC (American or Jap) PSone game is being played on a PAL (Europe, R.S.A.) PS2 the screen will lift up, meaning that a part of the top of the screen will be cut off. The amount that is cut off depends on the size of the T.V. On a 74cm T.V. about 100mm will usually be cut off. If a chip has the "screen center / fix " feature it will fix this problem for you.
     
     
     
       
      BOOTS ALL PS2 GAMES:
      Say no more. Please note that from time to time certain chips may have problems with some games. This is why "Flash upgradable" chips are normally the best choice. Normally cheaper chips have the most problems with imported original games.
     
     
       
      FAST BOOT MODE:
      When holding a certain button while pressing reset with a disk inside the console, the console will reset but not show any of the start up screens. Instead it will go straight to the first game screen.
     
       
      DISK SWAPPING:
      If you use a cheat device like an AR2 or Xploder you will need to put the cheat disk in the console first and after selecting the game cheat required you will have to insert the game disk. At this point the console will try to authenticate the disk and if the chip does not support "disk swapping" it will not boot the game.
     
     
       
      MULTI REGION DVD:
      Currently R.S.A. PS2s can only play Zone 2 DVDs. "Multi region DVD" will allow you to play all zones (DVDs from any country).
     
       
      MACRO VISION REMOVAL:
      When trying to record a DVD movie by connecting your PS2 to a VCR the screen will go black for a few seconds then the audio will go away and then some lines across the screen. This will carry on for as long as the VCR is recording, the moment you stop recording the movie will play as normal. This is what "macro vision" does. There are 2 different "macro visions" at work, the first is on the actual console, the second on the DVD disk provided that it has this type of protection. Since there's constantly new developments in "macro vision' protection it is not possible for mod-chips to remove "macro vision" on every disk.
     
     
     
     
     
       
      DEV MODE 1:
      Short for devolution mode. Crystal Chip, DMS, Matrix infinity, Ripper, LisaXP to mention just a few. This allows you to boot applications or software from a folder on the memory card. Take for example the PS2 reality media player which allows the console to play MP3s and DivX movies. Normally if you would like to use a program like this you will have to manually create a disk with the media player and the MP3s or DivX movies on it. You will have to do this for every disk that you would like to play. If you have a mod-chip that supports "devolution mode" you'll be able to install such a program to your memory card and also boot it from there by holding a certain button when turning the console on. This means that all your favourite MP3s and DivX movies can be thrown on a disk and played without having to create them in any special way.
     
     
     
     
     
     
       
      DEV MODE 2:
      A boot mode for the PS2 hard drive. Works pretty much the same way as devolution mode1.
       
      O.S, OPERATING SYSTEM OR BOOTMANAGER:
      A new browser for the PS2 which will allow the user to change video settings eg. if you are using an older TV set and the game plays back in black and white, then the default output can be changed to PAL to prevent this from happening. Homebrew apps can also be installed and un-installed from the O.S. or BootManager
     
     
       
      HOMEBREW APPS:
      These are software programs deigned by coders in their spare time. These programs are not copyright protected by Sony and do not belong to Sony at all. These programs are free and may be downloaded and used as required by the user. Since these programs are not PS2 games, they need to be booted in a special way. If a mod-chip has a devolution mode or O.S. then these apps can be booted from the memory card or HDD just by selecting it on-screen.
     
     
     
       
      STEALTH MODE (SWITCH OFF):
     

The mod-chip can be deactivated by the user. The console will behave as it did before a mod-chip was installed. There are 3 reason why this should be used.
.a) If an original game every detects the mod-chip simply turn it off.
b) If you would like to play games online. Some servers will not allow you on if your console has a mod-chip in it.
c) You can not install official Sony software or upgrades with a mod-chip installed unless it can be turned off.
     
     
     
     
       
      FLASH UPGRADABLE:
      "Flash upgradable" means to be able to update or reprogram the mod-chip via CD with the correct software on it. All you have to do is put the update disk in and the chip will do all the work. Earlier we covered the different I.Cs that can be used to create a mod-chip, but essentially the code on the mod-chip is what makes it. Mod-chip developers are constantly working to better the code or software on their mod-chips and when they do you can have these updates for free forever.
     
     
     
       
      HDD PATCHING:
      This is when a game installs most of it's files to a hard drive that is connected to the PS2. Note it will only do this if you have an official Sony hard drive. When you have "HDD Patching" enabled you can connect any computer hard drive not larger than 137 GB to your PS2 and the mod-chip will do a patching process to make the game believe that it's the official Sony hard drive.