If you have sound on XMB, you can try to blindly update your FW.
I don't think your VRAM died. In our tests and with the logs provided by Haxxxen, it seems like there isn't enough power supply for it. Try to provide us with a syscon log.
Personally, i think your console can be recovered as you can still hear that the XMB is working.
I'll make one today.
Update
@JoeSapecudo's system runs 900/1000 better than mine, but on Crysis, it randomly crashes after some minutes (It's rare, but it is happening). Therefore, we should assume that the latest stable clocks for 2511X are 850/1000. Although it works fine for most of the game, Crysis and GOW are experiencing these issues, so it's better to keep everything 100% stable.
I don't think it's worth pushing to 950 core, at least on our consoles. It may become stable in the future on Super Slim models, but I do believe we can still push the memory further. We haven't observed any artifacts in our systems, and overclocking the memory is providing a greater FPS boost than overclocking the core.
I'll create an updated table soon.
Important notes:
Keep in mind to observe the following:
If your console is reaching the memory clock limit, it will start artifacting. If you notice this happening, DO NOT push it further, as it will 100% brick your PS3.
If your console is reaching the core clock limit, it will crash in RSX-extensive games such as Crysis and GOWs. We haven't had any consoles bricked due to the core.
And, of course, test only incrementing by 50MHz each time.
One question:
If you've tested, let's say, 700/1000 and it worked, could we assume that the 1000MHz memory will work in all core speeds, right? As I could see, if a memory clock is supported, it will work just fine at every core speed, so there is no need to start from scratch in the next core increment.