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Konaguy
July 8th, 2007, 01:24 AM
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
July 8th, 2007, 01:39 AM
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 (http://www.pcpower.com/home/) is top shelf stuff. I tend to buy from a trusted store since power supplies are a commodity item.
Konaguy
July 8th, 2007, 01:49 AM
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 (http://www.pcpower.com/home/) 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
July 8th, 2007, 01:56 AM
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
July 8th, 2007, 02:03 AM
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
July 8th, 2007, 02:11 AM
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
July 8th, 2007, 02:26 AM
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
July 8th, 2007, 03:06 AM
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
July 8th, 2007, 03:31 AM
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
July 8th, 2007, 09:32 AM
Can a PS that's decided to finally not work actually fry your mobo?:confused:
GeckoGeek
July 8th, 2007, 10:46 AM
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
July 8th, 2007, 11:57 AM
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
July 8th, 2007, 12:23 PM
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
July 8th, 2007, 11:48 PM
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
July 9th, 2007, 07:21 AM
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.
Konaguy
July 9th, 2007, 04:09 PM
I called around, one place wanted 92.00 for a 430W power supply. With installation they charge a percentage ofa 65.00 hourly service fee.This
same place had a 250W PSU for 40.00.

The place I bought my computer at charges a 10.00 installation fee. I'll have to call them tomorrow to find out how much the higher watt power supply is.
Vanguard
July 9th, 2007, 05:05 PM
This
same place had a 250W PSU for 40.00.


It's nice to save money, but with 250 W you wont be able to support a decent video card, among other things. You could also do the math (there's a website somewhere that adds up the wattage of your proposed computer components to find out what kind of power supply you need).
Konaguy
July 9th, 2007, 05:13 PM
It's nice to save money, but with 250 W you wont be able to support a decent video card, among other things. You could also do the math (there's a website somewhere that adds up the wattage of your proposed computer components to find out what kind of power supply you need).

Oh I'm not going to be that much of cheapskate. I'm going to go and see if i can get an equal wattage PSU.
craigwatanabe
July 9th, 2007, 08:54 PM
Even at $39 that's fairly cheap. Look at NewEgg's customer reviews and see what are the good PSU's and what aren't.
Konaguy
July 11th, 2007, 03:13 PM
I ended up buying an Antec Smart Power 2.0 ATX 12V v2.0 400W PSU for 74.95.The PSU has two fans,one that blows cool air out inside. The other is facing out kicks in when the PSU gets too hot.

Luckily I replaced the old PSU. The dust was caked on the electrical components.
GeckoGeek
July 11th, 2007, 11:52 PM
Luckily I replaced the old PSU. The dust was caked on the electrical components.

You may want to consider re-locating the CPU. Places near the floor pick up a lot more dust then those at desk level. Either that or clean it out more often. A vacuum cleaner and a can of air would make short work of it.
Konaguy
July 12th, 2007, 02:30 PM
I think the problem should go away this time. As the PSU I bought has two fans.The inside one blows hot air out. If the PSU gets too hot, the second fan kicks in. I called them up just because I was curious when the other fan kicks in. The Antec tech support person said 50 ?
MixedPlateBroker
July 12th, 2007, 10:54 PM
If you want to help protect your fans from dust, there's an electronics supply store by the airport that sells foam filters w/brackets for your ports. They also have lots of raw cat-5/6 and pretty Flukes. :D
Altivec
July 13th, 2007, 02:58 AM
If you want to help protect your fans from dust, there's an electronics supply store by the airport that sells foam filters w/brackets for your ports. They also have lots of raw cat-5/6 and pretty Flukes. :DIC Supply on Ualena Street.
GeckoGeek
July 13th, 2007, 09:15 AM
I think the problem should go away this time.

As long as you have a fan, you'll have a problem with dust. The fact the fan only runs as needed and not all the time will mean it takes longer to build up the dust, but it will still happen.

You can use the fan cycling as a clue. I know certain machines at work when I hear the fans running on high more then usual - it's time to clean them. (But that has more to do with dust on the CPU heatsink then the power supply.)
craigwatanabe
July 13th, 2007, 11:20 AM
If you want to help protect your fans from dust, there's an electronics supply store by the airport that sells foam filters w/brackets for your ports. They also have lots of raw cat-5/6 and pretty Flukes. :D

Or just do what I do and pick up some air conditioning filter material available at any home improvement center such as HOME DEPOT (Frost King) or maybe umm Lowes or similar:D

Cut out a piece of it and either place it inside between the fan and the case or if you're lazy tape it to the grill on the outside.
Konaguy
July 16th, 2007, 03:05 PM
As long as you have a fan, you'll have a problem with dust. The fact the fan only runs as needed and not all the time will mean it takes longer to build up the dust, but it will still happen.


Even if the fan that is going constantly is inside the case. As far as I can tell,the heat dissipates out through the back. The fan in that same location doesn't kick on until a certain temperature is reached.
GeckoGeek
July 16th, 2007, 11:25 PM
Where there's a fan, there's dust. Bet on it.

If a fan blows air out, then the dust gets sucked in through any and all cracks in the case. Even fans that just circulate air in the case can get choked up by dust because the main fan pulls it in.
craigwatanabe
July 17th, 2007, 12:12 PM
This is why I think all fans should intake fresh air. Intake can be filtered and because of positive air pressure within the case hot air is blown outward.

The CPU fan will draw heat away from the heatsink but will exhaust within the case. A case fan should draw fresh air to displace the hotter air from within.

Right now I'm installing two fresh air 80mm intake fans with filters in my tower because I've located it under the desk where cool air isn't quite so apparent. P4s run very hot so good cooling is essential for these bastards.
buzz1941
July 17th, 2007, 12:54 PM
A bit off-topic, but I think I'm in the right crowd of geeks. Is there any place in Honolulu that deals in electroluminescent or EL cold lighting? Like LightSheet products.
GeckoGeek
July 18th, 2007, 12:09 AM
This is why I think all fans should intake fresh air.

Yeah, the original IBM was built the other way and we've been stuck with it ever since. I think it was because the very first ones used 120V fans and they didn't want to string the wire though the case so they put it in the power supply. Since they wanted to cool the case rather then heat it, they made it into an exhaust fan.
MixedPlateBroker
July 18th, 2007, 04:43 PM
A bit off-topic, but I think I'm in the right crowd of geeks. Is there any place in Honolulu that deals in electroluminescent or EL cold lighting? Like LightSheet products.

Give Ace Security Products (http://www.acesecurityproductshawaii.com/html/light_tape.html) on Alahao Place a try. The carry Light TapeŽ (http://www.lighttape.com/).:cool: