QUOTE(☼ ♣ Stvnkch ♣ @ Dec 31 2007, 09:03 PM)

for fat psps (which you have consdiering your on 3.40 OE-A) 3.52 M33 with update 4 is the best. your firmware should run gpsp 0.9 just fine.. the later gpsp kai test versions are for slim psp with tv output support and sue the slims 64 mb of ram. if you put the gpsp in the game150 folder on your mem stick and ahve the right bios it should run fine.. but I still recommend 3.52 M33-4 for your psp.
I agree with Stvnkch, because i am currently on 3.52m33-4 and its is great. It is better than 3.40oe-a and has the quick option to fix the cpu speed, ISO option, and the USB via without going to the recovery mode.