there are 3 100% way to repair "only NOKIA logo" problem for both 7610 and 6670:
-1-
- Full erase (also eprom and user area)
- flash with newest firmware
- upload good pm
- unlock and format user area
if problem still same then second way
-2-
- check or change N130 (especially when water demaged)
- if still same, do all -1- options after change N130
if problem still same then go third way
-3-
- make pm backup from 0 to 255 and save
- change flash chips by order bank1 and bank2
- flash phone with last firmware
- create RPL with the soft PM to RPL by invisible( thanks to invisible,
http://invisible1.da.ru)
- upload RPL and calculate flash IMEI
- unlock and format user area
that's all. good like!