May be that you'll need to go the complaints route, mentioning the CRA.
Mentioning that you're not raising it as an expired warranty issue, but that you'd reasonably expect the machine to not fail so soon through normal use etc.
Did you buy it with a credit card? That might be a route if Dell are unhelpful and you've shown that you've given them an opportunity to do the right thing.
May be that you'll need to go the complaints route, mentioning the CRA.
Mentioning that you're not raising it as an expired warranty issue, but that you'd reasonably expect the machine to not fail so soon through normal use etc.
This stuff
https://www.moneysavingexpert.com/reclaim/consumer-rights-refunds-exchange/
https://www.moneysavingexpert.com/reclaim/how-to-complain/
Did you buy it with a credit card? That might be a route if Dell are unhelpful and you've shown that you've given them an opportunity to do the right thing.