Maybe, but I don't think it's very probable. Dosbox, I think, does not stress the graphic card too heavily. Even my radeon 9600 pro could output anything under DosBox with any shaders that come with it in the resolutions I used it (1024*768, 1280*960), and my geforce 8600 gt can do 1920*1200 without virtually any performance loss (well, if I run SuperEagle shader 640*480 Blood start position framerate drops from 49 to 46-48 or something similar, the interesting thing is that it doesn't matter at all if I accidentally leave 8xQAA on 😕 ok, it's just 2 triangles, filling the screen once per frame 😀)
I can't say anything about GPU fans, I use passive cooled vcards 🤣
But DosBox uses the CPU much more intensively: on singhe core CPUs it should be 90-ish per cent running it at auto speed, and something like 40-50 on dual cores or HT enabled processors (it tries to use one of the cores to its fullest) (damnit, I forgot to have a look at its CPU usage on my shiny new Conroe-based rig, but on my AthlonXP it definitely used around 90%)
Those drops in the CPU usage might indicate that something runs there that shouldn't 😒 or it should, just it has an impact on DosBox performance. My single core AthlonXP usually ran uTorrent and boinc alongside DosBox transparently, but a virus scan can be more demanding.
Shame on us, doomed from the start
May God have mercy on our dirty little hearts