Bricked ps3, what now?

Hey,

I just tried converting back from dex to cex and I failed so now my ps3 is bricked, it beeps then stays on for about 30secs and then goes off.

If it helps i have back ups of the nands and lv1 and lv2

I cant access the recovery menu.

Is there anything i can do? I have a custom psp if that helps as well?

I have a nand ps3.

thanks