Lenovo Yoga C740-15IML Random shut downs

[nlinecomputers]

I have a Lenovo Yoga C740-15IML laptop on my bench. The EU states that it is randomly shutting down. He said it was just blanking the screen but the two times I saw it the unit had fully powered off. You are working along and suddenly the screen flashes, random pixeled squares pop up and then it powers off. Sudden instant death. I have run diagnostics using Lenovo Vantage, the Windows memory test, and ran a program called Heavy Load to test, and all passed. Only on actually use does it seem to power down. I opened the unit and replaced the heat sink compound even though it looked in good shape.

I am guessing motherboard because what else???

Any thoughts? These things are crap like most store-bought Lenovos. If it don't say ThinkPad they are junk.

 

[Larry Sabo]

I watched a YouTube video yesterday about a Yoga 900 whose screen flickers then goes blank but it keeps on running, so I don't know if it will be of any help. Anyway, might be worth checking the screen cable and LVDS connector. Sure sounds like a motherboard fault to me.