hi to everyone, i am a newbie to this website and i need some help.. i ve bought a bios free zone from bad_ad84, and it is not working, all i have is a black screen. i followed the tutorial very well, i triple checked with a magnifier my soldering, no trace broken, checked with multimeter all legs and traces, connections to other chip, points on main board and i can fairly say all i good no mistake from me... the motherboard is 171 - 7069b main 837-11892-01 pal... do you know if there is any issue with the bios free zone and this model? it seems some french people are having the same issue with this main board.. coincidence? I did the 50/60 hertz switch before that and didn t have any trouble. hope anyone can give me a hand! thanks a lot.
Modded many VA1 boards, PAL and NTSC. Every single "My soldering is fine" issue I have had, have all been soldering issues. Send me just the motherboard and cover return postage and I will look at it for free. Just because if I get it working, I can send this thread to others who have issues.
VA1 boards have a notorious board design error for the 50/60hz mod by the way, in that they have the SW4 switch, but it is still connected to the PLL pin, which needs to be raised and grounded (or you can just solder your switch to the VDP2 pin). If the PLL pin is not grounded, the machine sometimes not boot, just maybe on the 2nd try or so - it's random, on some machines you can just cut the pin and it works, on other it needs to be grounded. Probably related to some nearby caps, as the trace travels under a bunch. But if you had the 50/60 mod installed previously, and it worked, then simply swapping the bios shouldn't be triggering that fault. You should at least post pics of the board. We need to save this quote for prosperity somehow.
I'm betting on soldering issues myself, not seen any problems with swapping out the BIOS that could be tracked back to the BIOS itself. Usually is a problem in the waiting that removing the board and handling it causes to crop up.
