True, oil does not account for the majority of electricity generation, however it is used to meet short demand-increases (consumption-spikes). But what do you think will happen when oil-prices start sky-rocketing? IMHO cunsumers will start to switch their oil-powered devices to electricity, which might very well create a severe price-increase in electricity as well.
Also much electricity is generated from natural gas, which is expected to peak just a few years after oil. And oil is also used to build and maintain power-plants and to obtain their "fuels" (like uranium or coal).
Finally great amounts of oil and oil-derived chemicals are used to make computer chips, so computer chip prices should increase with the chips size. ARM chips are very small and so a lot more of them can be made from each wafer than x86-chips.
But all of this may be irrelevant, if the oil-shortage should lead to a collapse of the global economy and we might have to obtain the power to use computers our selves, for example by using the photovoltaic cells on our rooftops, if you were fortunate enough to obtain some before the oil-crash, or a hand/feet-powered generator. In this scenario I am glad I have an a9home and a flat-screen which I could rig to use natural light instead of the built-in back-light.