Issue with Legion Y720

Hello everyone,

Posting this to see if someone experienced an issue like mine with a Legion Y720 laptop.

First of all, my Laptop is a Lenovo Legion Y720. I did a repaisting with Arctic Cooling MX-4 plus undervolt of -0.120V only to the CPU using XTU and a Powershell script which ran with a Scheduled Task each Windows Login.

Temps were always very good for an i7 7700HQ, never passed the 80° mark, I think the cooling system of this Laptop is OK.

So I'll try to explain the issue, about a month ago while I was playing I began to experience video and audio stuttering (I don't know if this is the right term... something like a very aggressive audio and video lag), so I closed the game and started to troubleshoot the issue to try and find what was causing it.

Temperatures were OK for all the hardware. Taskmgr was OK, CPU / GPUs / Disk / Network / RAM, everything 0% but for example when opening Chrome the CPU would go from 0% to 100% for about 5 seconds. My first guess was that the issue was related to Nvidia Optimus so I downloaded DDU and went to safe mode to perform a clean installation of the Intel and Nvidia drivers (now this stuttering wasn't only while gaming, I could barely navigate and took a very long time to download DDU... Mouse was also laggy and input keys were laggy too). Now when I logged in to safe mode I realized that this issue was bad, because it persisted even in safe mode... anyways a proceeded with the clean reinstall of vide drivers which didn't solve the issue. So I turned off the laptop, went to bed and to work the next day. When I came back from work the issue was miraculously solved like WTF. After a month of everything working excellent last Thursday this issue started again so this time I began with hardware testing. Memtest was OK. Disk was OK so yeah I kinda suspected from the beginning but didn't want it to be true that this was a motherboard issue anyways I remembered I don't know why about the undervolt and about the scheduled task so I put everything back to 0 and disabled the task, restarted the laptop and everything started to work just fine again after a few windows restarts that issue re-appeared so I opened the laptop and removed the SSD I was using (1Tb Samsung EVO 850) and installed the HDD Seagate that came with the laptop. With the Seagate Windows wouldn't even start so I tried resetting Windows and it started still with the same stuttering but now also I tried to for example connect my external monitor or even connect a mouse or external keyboard Windows would hang and Windows would not even start with a peripheral connected. So now the Lenovo is in the warranty.

Ok, I'm sorry for the very long post but any guesses are very much appreciated. I don't know if this issue can be related to undervolt or just I got a faulty laptop. Maybe all the Legion Y720 shipped to Argentina are all faulty or maybe not.

 

Try clean install windows

 

Already confirmed with Lenovo Warranty Service, this was a motherboard issue as I suspected. Windows install would not work, already tried that.