RE: Attn: XPS 8700 Owners - Upgrade!!
Can you post a screenshot of CPU-Z when under load showing the CPU voltage? I'm mostly curious how much the OEM board can deliver.
and, there is a feature of CPU-Z where you can "validate" your CPU and post it up to a web page and it will show all the details and will give you a link like this:
The link above is my non-dell 4790K.
cpu-z can be found here:
And, on the front case fan, I replaced the rear fan in one of my systems with a very quiet Noctua fan:
and then used the stock fan in the front of another 8700 system. I used a Y-connector and a fan extension so it runs off the same fan header as the exhaust fan.
This system has a GTX 770 that is overclocked and it runs rather warm. Hoping the second fan will help.
If this doesn't help, a larger effort is to cut away the front of the case and add a 140mm fan but I'm not really looking forward to doing that.