what is the list of app on the machine that you have running... How any monitors are you running with it ?
Perhaps your fault for not listening to Scatty. I've advocated the Precision line of Dell for both desktop and mobile workstations. If you try to "go cheaper", you get what you get. (I had a couple of Dell "el-cheapos" 10+ years back... but I never recommended them nor bought another.) Dell Precision has always been their best Business/Enterprise line.
As mentioned, make sure you have everything on a fast SSD drive, if it came with a normal hard drive, I would actually remove it and add another SSD drive. Also, make sure you update the firmware, it does not get updated automatically and should be done once per year.
pulled a trigger on precision mobile 7670 default model with i-7 and 4k screen upgrades and sodimm, good value performance ratio i hope.
the touchpad is off center to the left side, i constantly hit the center, which is the right side of the touchpad, none of the usual clicks can be programmed to the slightly right. i guess i have to get used to or use a mouse.