(adsbygoogle = window.adsbygoogle || []).push({}); So I have a cech 2501a slim running on 4.78dex untill my hard drive took a crap. My issue started with the screen freezing, then when I would power on the light would turn green then instantly shut off. I started with a new power supply but that was no help so I bought a new hard drive installed powered on and it stayed on. Says to connect controller, then when I connect it says to restart or install firmware of 3.40 or higher. But I have tried everything but it keeps saying no applicable data found.......What do I do??

1. Have you tried installing the 4.78 firmware again..

2. Try installing the Dex downgrader or similar downgrader.

I had to change my Mac address and had to get back to 3.55 but I used the 80gb hard drive that came with my ps3 when I bought it. but I couldn't get 3.55 to go on it but the dex downgrader worked for me lol. So being as you were still on Dex. Try installing the Dex downgrader then go 2 3.55 kmeaw then back to your firmware that you were on.

Also make sure in your usb you have the folders like

PS3
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