PCG-9G1L SONY white screen want to know factory reset sequence

My Vaio has a black screen. Is it fixable?

Not too sure what you mean here.you can reset bios to default or can set bios to factory reset.to set default ...when you turn on pc ,message at bottom left hand screen indicates which key to press to enter setup(bios setup) note...its very brief;mines f 10 for instance.at startup press this key and select load default then select save settings and exit;then ur pc restarts with default settings.
To reset bios to factory requires disassembly.
you locate rtc and remove battery(looks like large watch battery)for 5 minutes then replace,reassemble and restart pc.you dont need to know what rtc means(real time clock)or what it looks like cos the battery is right next to it.