Computer Power Supply Question

[Konaguy]

Since I use my computer way too much, I was looking at buying a new power supply. The computer is a bit over a year old, is a ATX Mobo and has a 430W
power supply. I'm curious what kind of power supply I should be looking for.

[GeckoGeek]

Re: Computer Power Supply Question

Uhhhhh, I'm missing the logic here. You just want a backup in case the one you have packs it in? Why do you want to change a working power supply?

If you're looking for recommendations, I've heard PC Power & Cooling is top shelf stuff. I tend to buy from a trusted store since power supplies are a commodity item.

[Konaguy]

Re: Computer Power Supply Question

Uhhhhh, I'm missing the logic here. You just want a backup in case the one you have packs it in? Why do you want to change a working power supply?

If you're looking for recommendations, I've heard PC Power & Cooling is top shelf stuff. I tend to buy from a trusted store since power supplies are a commodity item.

I know it doesn't make much sense. But my last computer's power supply died prematurely.It was slightly less than 2 years old when my previous computer's power supply died. It fried my Mobo also rendering my previous computer dead. So I'm a bit skittish when it comes to power supplies.

I'll check out the link, thanks.

[GeckoGeek]

Re: Computer Power Supply Question

A decent power supply should last you until you decide to upgrade the machine. I've seen plenty of failed power supplies. Usually they won't take out the mother board, but it has been known to happen.

[Konaguy]

Re: Computer Power Supply Question

Yeah I learned the hard way.My previous computer was this Compaq Presario.I found out later the power supply was on 24/7. There was this light always
on the back of the computer behind the power supply. I suspect that was why it failed prematurely. My new computer has the ability to turn off the power supply.So when I'm pau, I turn the power supply off.

[GeckoGeek]

Re: Computer Power Supply Question

I found out later the power supply was on 24/7.

That's true of all of them since the ATX setup. A small supply is on all the time so the some things remain powered up. The main power supply turns on and off with the computer.

Heat is the big enemy of power supplies. Especially if they have to run when it's hot. The heat cooks the caps over time and they fail. It doesn't help that some manufacturers scrimp and use cheap caps.

Of course, when I say "heat", I also mean things that block the airflow. Like dust.

[Konaguy]

Re: Computer Power Supply Question

That's true of all of them since the ATX setup. A small supply is on all the time so the some things remain powered up. The main power supply turns on and off with the computer.

Heat is the big enemy of power supplies. Especially if they have to run when it's hot. The heat cooks the caps over time and they fail. It doesn't help that some manufacturers scrimp and use cheap caps.

Of course, when I say "heat", I also mean things that block the airflow. Like dust.

So when I flip the on/off switch on the power supply its still on ? I ask that question because if I don't flip switch my optical mouse and
speakers remain on. If I flip switch all therm turn off.

I just spent some time trying to clean the dust out of the fan on my power supply.

[Vanguard]

Re: Computer Power Supply Question

If I was in the market for power supply, I would want at least 500 W. But I like a diverse set of applications, including games once in a while.

[craigwatanabe]

Re: Computer Power Supply Question

When you turn off that rocker switch on the power supply you shut off all power to the MOBO.

Your Presario PSU probably bit the dust because it was a cheap PSU that came with it right? Compaq usually installs 250-280watt PSU's in their budget computers. That is not enough to run a decent P4 computer using all your available USB ports and running a DVD burner.

Typically the +5vdc output is the most common one to die on most PSU's. Sometimes the +12vdc one fries and that can shut down the CPU cooling fan which will lead to a CPU overheating and there goes that chip.

You gotta keep that cooling fan clean. Dust buildup on the fan blades can cause drag on the motor eventually killing it.

Some BIOS will sense a failed CPU fan and will not allow you to boot up until it's resolved.

You should be okay with your 430-watt PSU. If you want to preserve it run your computer on an UPS so it'll protect it from surges. That's the kind of things that will kill any PSU.

[cezanne]

Re: Computer Power Supply Question

Can a PS that's decided to finally not work actually fry your mobo?

[GeckoGeek]

Re: Computer Power Supply Question

So when I flip the on/off switch on the power supply its still on ?

The rocker switch ON the power supply does turn everything off. Or, a mechanical switch on the front panel. If the on/off switch is a "lightweight" push button, (feels more like a reset button) it doesn't turn it off.

I think the failure mode most likely to cause trouble is when the +5 caps give out. The cause increasing ripple and the average voltage drops. This causes the power supply to "open up" more to bring the voltage back to +5V, but results in the other voltage such as +12V to climb yet higher.

There is a crowbar circuit in there that's to prevent the power supply from going over-voltage on a failure, but all the supplies I've dissected, it only monitors one voltage.

[Konaguy]

Re: Computer Power Supply Question

I just spent some time trying to clean the dust buildup in my current computer's PSU. I think along with the cheapie PSU the Presario had, dust build up killed the Presario's PSU.
So, besides Gecko Geek, anyone else have recommendations for where I can look for PSU's.

[Konaguy]

Re: Computer Power Supply Question

Here is what hardware my computer has :

MSI Micro ATX Board SIS 661FX + 964 Chipset Based
2.8GHz Celeron
1GB RAM
30GB
150GB HDs
12X DVD+R/RW
128MB nVida Video Card
Floppy Disk Drive
There is two fans. One on the CPU and another on the rear.

[craigwatanabe]

Re: Computer Power Supply Question

go to NewEgg.com and stay away from even the cheap PSU's they sell. I bought four A-Power PSU's from them rated at 500-watts and two of them bit the dust within a couple months. One is still running strong and the other is still new in my storage shed.

As for PSU's frying motherboards, YES the can. With all the voltage regulation going on and when one regulator craps out there's a good chance of sending higher voltages to things like your memory modules (seen that happen once).

I agree with GeckoGeek that the primary fail in most PSU's are the filter caps. Cheap PSU's use really cheap capacitors that can deteroriate in moderate heat.

[Konaguy]

Re: Computer Power Supply Question

A quick question is 39.89 too cheap for a PSU. I did some checking locally, the place that built my computer is selling PSU's for that price. The other place I'm aware of they sell PSU's for over 100.00.