I have exactly the same model alienware like you and the same issue happened to me and I changed to 330 watts
and I asked dell support they just changed to 330 watts without any knowledge it works better than 240 watts in game and charge but I have now other issue which is : Coil whine, also known as electromagnetically excited acoustic noise and vibration or audible magnetic noise, is one of the most frustrating phenomena in modern technology. As its name suggests, this high-pitched noise is caused by electromagnetic coils that act as inductors or transformers.
It makes sound loud while gaming at first I thought its HDD but I was wrong.
check here one of my story with R5 :
We've seen users who have changed their adapters to the wattage mentioned (330W) and have successfully transferred the power requirements to the adapter only. However, this is not necessary considering that the PC can supply the entire power with this feature.
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