Sony Updates Its PSP Console with Firmware 6.61 – Download Links Available
PSP Custom Firmware 6.00-6.61
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Infinity 2.0 released for the PSP, allows for persistent CFW on all models of PSPs on 6.60 and 6.61 | GBAtemp.net - The Independent Video Game Community
Release: Infinity 2.0 – Enables Permanent 6.6x Custom Firmware for all PSPs! - Wololo.net
PSP - POPSloader 6.60 PRO (PS1 on PSP) | PSX-Place