The old NIOS development kit, Stratix edition: factory demo image.

I have some of the boards, but one of them isn't able to run the demo code, there are no blinking LEDs.
Moreover,  the factory demo images of both NIOSII EDS 5.1 and 7.0 didn't work, that's funny.

After reading back flash from one of the boards, the backup factory demo image worked as expected. But one other board is still not able to run code, stay in an ambiguous state (CPU reset state?), factory safe LED lights.

Are there some things to check by the factory demo image? Why does it hold on running the factory demo code? SDRAM failure? The user bitstream (no NIOS II) is OK to run from the flash.