Wat happen to my PSP?

My less-than-2-months-old GOW PSP got problem.

My problem that worries me started yesterday.

I have no problem playing UMD games.

From memory cards, few games like batman and indiana jones lego, silent hill, to name a few work smoothly as usual

but games like tekken, ninja turtle, buzz quiz, loco roco, street fighter to name a few too heavy (too slow) to play. Anyone know wat seems to be th eproblem?

my set is modded by SCE and running on version 3.99.
I reformatted my memory card and even bought new card but problem still there for games mentioned above. Set never drop...

help please... or i just come to your shop this morning ehehe

HI,BRO,
U CAN BRING BACK TO ME ,AND I CHECK IT OUT FOR U ,MAYBE IS U VERSION PROBLEM ,THXS