Device has been freezing in weird way

[kern417]

My phone has been freezing a lot lately. while doing regular tasks it will lockup and the screen becomes completely unresponsive. it completely locks up and the werid thing is i can't even turn off the screen. before when my screen froze i could still turn off the screen using the display on/off button and it would dim/brighten the display when i tapped it. I can't think of anything that i've added recently that could cause this...i tried removing android, and it was happening before i installed the overclocker (i thought it would help, but no cigar) and it is happening on multiple ROMs i.e. MightyRom FF, Vin's Plutonium...is this sort of problem associated to any specific application? I'm really trying not to buy a new device, but i didnt buy it through Verizon so i dont think i'll be able to replace it under warranty or anything like that.

edit: I think there is something wrong because when i think about it, sometimes after soft resets my backlight settings have changed themselves. for instance i have it set to dim after 10 sec and turn off after 1min but after a soft reset i checked and the 'turn off after' setting had been unchecked mysteriously...