Lets say you have custom firmware installed, and you already have some free PSP games in your PSP game folder. But during the game play you discover the game is slow; its choppy and interrupts the flow.
So how do you avoid the game lag? The only solution is to uncompress/decompress the game file into a standard format and transfer it to your genuine memory stick.
Let me explain a bit: The .iso game files, in most of the instance, never lags. Therefore converting your game file into iso is the best option to minimize or completely eliminate game lagging on your psp device.
Check your iso game folder, there is a possibility that the lagging game you’re playing is of .cso file extension. Usually CSO Files are best used for compressing the game, and because of the same reason the game lags or slows down when in action.
Converting CSO to ISO File
Uncompressing file gets easier with PSP ISO Compressor freeware, and if you’re facing any problems in setting up the software then check out the solution posted here. Once uncompressed to .iso format, re-transfer the game onto your psp and I am sure the game would run flawlessly.
However, there is a downfall of converting cso into iso file format, i.e., it results in larger file size. While uncompressing one of the game file from cso to iso, the original cso was 500mb, and it was 800mb after uncompressing to iso format. The difference might not be huge for some, but people using 4GB memory stick or lower might sense the difference.