Can a bad power supply affect the system start up/ turn off

[rabisccando]

I recently bought a cheap power supply for my desktop, but as soon as I changed it, I started having problems with booting, the computer wouldn't boot or took ages to boot (even in BIOS I couldn't enter) and it sometimes had problems to turn it off as well, It wouldn't turn it off unless I press the button.
(If I took off the energy cables and put it on again it'd work faster). Doing some research I found out that the power supply I put on my pc was under voltage. I went to those sites that calculate it and it said I need something around 330W and the one I was using it was like 200W. That 200W supply I was using, I somehow screwed it and I want to buy another one. What I wanna know in fact, is those booting symptoms I mentioned earlier, cab be anyhow related with the under-voltage power supply, or a bad power supply? Or is likely to be a coincidence?

 

[Ralston18]

Yes.

Either an under wattage PSU or a malfunctioning PSU (not providing the necessary wattage) can cause all sorts of problems.

Mainly because the output is provided at three different voltage levels: 3 volts, 5 volts, and 12 volts.

Can be difficult to predict or know which way things can happen and all the more so with a low end PSU.

Read some PSU tutorials and reviews via this Forum and others. You will learn more and likely to be able to make a more suitable purchase decision.

 

[terry4536]

Don't skimp on the power supply. Being under-powered is primarily going to affect the graphics card. But an erratic power supply can cause problems. It will also stress the components. A power supply with a bit too many watts is better than the other way around.

What is the component list? What is your budget for a PSU?