I modded my first V15 (SCPH-77001) today, modded many many PS2's, Xboxes, Gamecubes previously.
The install looks good, soldering looks solid etc. Here is the weird part.
When I first booted it, I held down to buttons to access the mod chip menu and it came up fine. When I rebooted, all I got was a black screen (like if it was installed wrong). I turned it on and off about 5times and kept getting a black screen and nothing else.
Then I held down start when turning on the system to disable the chip (don't know why I tried this instead of going back to check my soldering work). Well it came up saying the chip was disabled (like it should), and then the system worked fine with the chip disabled.
So I turned the system off and on, and now the system works fine with the chip enabled. I have tried many games, rebooted and powered the system on and off about 50 times and everything seems to be working perfect now.
Anyone ever heard of this problem before? The system has been working perfectly since that initial problem and I have yet to have another problem.