MK808B black screen until powered by laptop.......?

[voorstad]

For months I have been using the original MK808B with Finless1.6 without any problems. Suddenly, I had a black screen and rebooting over and over did not solve the issue. Blue led is burning, screen remains dead.

I first bought a new high quality HDMI cable, but this did not solve my issue. I then tried different adapters, but none of my adapters (original 2A adapter, Nexus 7 2A adapter, 2 other 1A adapter, a Belkin powered USB hub), nothing solved my issue. Blue led is burning, Hdmi output remains black.

I then wanted to see if my pc recognized the MK808B at all. I plugged the USB cable into my laptop and to my big suprise...... the Androidstick started, and showed the android desktop. Just by being powered by my Laptop USB.

I am puzzled. Anyone who can explain the above? It is reproducible and I have no other devices connected to the stick. The above occurs both when using the mini usb as the otg mini usb port.

Thanks for your thoughts.

[JDfense]

Sounds not good. Possible problem with the graphic chip or hdmi connection.

But at first I would try to reflash the stick with stock ROM or finless ROM. Maybe only the ROM is broken in nand flash and you need a fresh formatting.

JDfense

[jjfodi]

Any updates?

I'm running into a similar issue. I have been running an MK808B with Finless 2.1 for months as well. Typically in the first few minutes I'll see either a screen freeze or a black screen and the device becomes unresponsive. I have to pull the power to reboot (in fact - strangely - I need to pull the power from the power supply - simply unplugging at the device does not cause a reboot). Sometimes the power to the attached devices (mouse and keyboard) is lost. I've tried multiple power supplies. Also - just reflashed (successfully) and same symptoms. I'll post to a separate thread - but this sounded very similar.

[mo123]

I'm running into a similar issue. I have been running an MK808B with Finless 2.1 for months as well. Typically in the first few minutes I'll see either a screen freeze or a black screen and the device becomes unresponsive. I have to pull the power to reboot (in fact - strangely - I need to pull the power from the power supply - simply unplugging at the device does not cause a reboot). Sometimes the power to the attached devices (mouse and keyboard) is lost. I've tried multiple power supplies. Also - just reflashed (successfully) and same symptoms. I'll post to a separate thread - but this sounded very similar.

You either don't have a real 2A power supply or your device overheats, try better ventilation by blowing cool air with a fan over the device.
Do you have an original MK808B with a heatsink?
You can try to flash lewy20041 HFW 2.2.4 rom and try to underclock your device with SetCPU to see if it helps.

[jjfodi]

Really appreciate the quick response!

I have two MK808B devices - so have a backup power supply to test with (the other device is working well). I've swapped the power supplies and the older MK808B is running fine on the new power supply. Hopefully - that rules out the powersupply issue.

I purchased in mid-June 2013 - so I believe this is the newer MK808 with the heatsink.

The device doesn't feel hot. The room temp is approx. 65 and I've ensured the device is positioned such that no air ports are blocked, as well as turned on an overhead fan. It used to run without issue in warmer conditions (same room during the summer) - but it makes sense that it would be temperature related since it seems to freeze/black screen within the first few minutes. Possibly there is an issue which is exacerbated by temperature?