I have had considerable experience with Dell in the past 35 - 40 years, all bad.
Their machines support only , and I mean only the components they put in them. If your power requirements increase your going to have problems. For the past 20 years people come to me with problems on their Dell machine, laptop or desktop. My comment to them is; "You have my sympathy".
Knowing what I have experienced, I would say it is lack of power.
If it ain't broke; don't fix it!