UPS beeps constantly while playing.
You may want to just try plugging your Tower only into the backup. That is a fairly low end battery backup, that isn't really designed to have a whole bunch of power being pulled through it.
As far as how it will do being plugged directly into the wall, well mine is that way now, I used to have UPS but the good ones are expensive and I don't have the spare cash to replace so yeah it will work. But then again, the power grid in my area is fairly stable, and the outages and brownouts are few and far between. So it depends on the condition of your power grid for your home. If you have lots of outages and worse yet brownouts(that half lit when power is sorta still on but not really) then you really need to have an UPS to prevent all sorts of issues. If you are in a stable area, then most likely you can get by without it...just turn off for storms and such..
Just to let you know, that UPS is only good for about 2-5 min backup...anything longer and it will shut down, which makes it about useless for anything other than giving you a second to shut your system down if you are right there, and to cut down on spikes or flicker outages causing issues.
