  Using cosmological hydrodynamical simulations at $z\sim0.5$, we measure the
thermal ($b_{t}$) and non-thermal ($b_{nt}$) contribution to the line
broadening for the intergalactic absorbers having \OVI\ and \HI\ absorption
well aligned in the velocity space. We find that the inferred temperature based
on $b_{t}$ correlates strongly with the optical depth-weighted kinetic
temperature of the absorbing gas, albeit with a large scatter. We show this
scatter comes from the spread in the kinetic temperature of the gas
contributing to the absorption and hence depends on the feedback processes and
the ionizing UV background (UVB) used in the simulations. We show the
distribution of $b_{nt}$ is also affected by both feedback processes and the
ionizing UVB. Therefore, $b_{nt}$ derived using aligned absorbers may not be a
good probe of sub-grid turbulence. Therefore, $b_{nt}$ derived using aligned
absorbers may not be a good discriminator between the effect of microscopic
turbulence and UVB. Instead, the distribution of $b_{t}$ and $b_{nt}$ together
with the frequency of occurrence of the aligned absorbers can be used to place
additional constraints on the parameters of the simulation for a given assumed
UVB.
