Unbricking AR750S

I replaced the AR750S router I used at home with a MT1300 some time ago. I now wanted to set it up as a travel router. Following the steps to get into uboot, pressing reset while booting, I see one of the LEDs flash five times just as it should, then the two other LEDs are on. I think this also looks correct. However I cannot connect to or even ping that IP. Yes, I am connected to the AR750S (I tried both LAN ports as well as WAN) and set on my notebook. Any idea what could be wrong? Could the box be bricked even when the LEDs seem to work fine?

I cannot tell by your post what OS you are using. If it is an old AR750s, per this post you can only use Windows.

Several people have reported that by trying a different system, that uboot magically worked for them.

Wow, that was unexpected. Thanks for the information.