A z-wave Appliance Module would work fine. Do not use the lamp modules as they are dimmable. The appliance module has a relay to switch devices on and off.
I know the GE dimmable switches do “soft” turn ons (The dimmer is turned up from zero, even with an on command). I have not tried any of the lamp modules. The other issue with the lamp modules is their rating is typically much lower than the appliance modules. Although their rating is probably ok for a computer that is on, some computers take a larger amount of power on power on. This could exceed the rating of the dimmer and lead to short life.
For my case, what I am attempting to do is turn a wifi repeater on and off to reset it (it’s a bit flaky), and it draws very little power. Might work well for me if it doesn’t “ramp up”. Thanks.
By default the dimmers ramp up and down, even when just switching them on/off. Depending on the dimmer, that behavior can be changed and you may get something close to on/off, but it is still not a relay. I wouldn’t hook a computer power supply to it.