Question Power issues ?

cool09

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Jun 27, 2010
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Recently my power works maybe 50% of the time. And I'm getting a BIOS screen when my ASUS PC boots which I don't understand: it tells me to enter Setup. I hit F1 and then F8 to boot the PC and it boots fine.
I have an ASUS PC which is about 5 years old and I don't know what type of Power Supply I have (System Information doesn't tell me).
Do I need a new Power Supply?
 
If the CR2032 battery has gone flat, the BIOS will forget some important settings and prompt the user for action (Press F1). You might notice the PC has "forgotten" the time and reverted to some random date in 2019, etc.

When healthy, the CR2032 keeps the Real Time Clock running. If the time is wrong, Windows resets the clock from a network server, but the PC forgets the time again when you power down, if the CR2032 is dead.

F8 might be the BIOS option to select the boot drive. With a flat battery, the BIOS will lose the boot order table and the first item in the list might not be your Windows drive. Hence the F8 prompt.

A healthy CR2032 will be around 3.25V. I replace batteries when the voltage drops below 2.50V. A flat battery will be less than 1V.
 
Yes, the date and time changed on the PC last week. Today, PC will not start at all. Yesterday, PC ran and I left it and came back and screen was black and I hit mouse and keyboard and screen would not start up. I will replace cmos battery.
If time is wrong PC will not power up?
 
If time is wrong PC will not power up?
It's more the fact that when the CR2032 battery is flat, the computer often "sulks (as I term it) and refuses start.

Incorrect time/date settings do not usually prevent a computer from starting up, so long as the CR2032 battery is healthy.

If I buy a second hand motherboard and it doesn't have a battery, I fit a fresh battery and check the BIOS. The time/date is often set to some arbitrary time/date in the distant past. I set the correct time/date, save the settings, then install Windows.

During normal operation, Windows usually updates the Real Time Clock using "Internet Time", if the BIOS time is wrong.

If nothing else has failed, a new battery should restore life, but you may have to tweak a few settings which the BIOS has "forgotten". A typical example of lost settings is the drive you want to boot Windows from.

Sometimes after losing its memory, the BIOS will revert to booting from "Network", "Optical Drive", "Floppy Drive" (in the dim and distant past) or some other non-bootable drive, instead of your Windows drive. You need to find and set the correct (Windows) drive as the first boot option. Remember to save the settings when quitting the BIOS.

To sum up, if an old computer seems dead, I check the BIOS battery voltage with a digital multimeter set to the 20V DC range. It's easy enough to do. Positive lead to the top of CR2032, negative lead to chassis. If the CR2032 voltage is less than 2.5V I replace. A flat battery is usually well below 1.0V.

N.B. When fitted correctly in the battery holder, the '+' symbol on the CR2032 should remain visible. The negative side of the CR2032 remains hidden inside the holder. You must install the CR2032 the "right way up".
 
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Replaced CMOS battery and PC won't power up. Checked Power Supply connection to motherboard and it was ok.
Is there a way I can check Power Supply with a voltmeter? PS says AGW650 on the side.
 
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Is there a way I can check Power Supply with a voltmeter? PS says AGW650 on the side.
You could try the "paper clip" test, but it won't reveal certain problems (excess ripple voltage, faulty overload protection, maximum power capability).
https://www.wikihow.com/Check-a-Power-Supply

The "paper clip" simulates pressing the power button on the computer's front panel. You can check the +12V (yellow), +5V (red) and +3.3V (orange) rails with a multimeter, if the PSU starts up.

Unplug both power cables to the mobo and any SATA drives, USB hubs, LED fans, etc., then apply the paper clip.

If the PSU fan doesn't start up, that doesn't mean the PSU is dead. Many PSUs don't start the fan until power output exceeds circa 300W or the PSU gets hot.

If any of the voltages are outside these limits, it's probably time to get a new PSU, but you're testing the PSU with no load, which is not representative of normal operation.

iu


Aresgame PSUs do not have a very good reputation. I'd advise buying a better quality PSU, even if the AGW650 still works.

Review of an 850W Aresgame.
https://www.tomshardware.com/reviews/aresgame-ags850-power-supply-review
 
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When I tried to start PC with new cmos battery the screen lit up for only a second and fans did not start at all.
After you replace cmos battery does the date and time have to be set manually or does it automatically detect them?
How do I determine what size PS I need?
 
When I tried to start PC with new cmos battery the screen lit up for only a second and fans did not start at all.
Have you run the "paper clip" test yet with the power cables disconnected from the motherboard.

If not, we still don't know if the PSU is "working" or not. It could be on the point of catching fire.

If you read through this post on Tom's, you'll see the AGW650 is regarded as junk.
https://forums.tomshardware.com/threads/anyone-got-info-on-the-aresgame-650w-power-supply.3674079/

You're lucky to have got 5 years of use out of it. Replace it now before it explodes. It may already have damaged your motherboard beyond repair.

After you replace cmos battery does the date and time have to be set manually or does it automatically detect them?
As I've already explained, you can set the time manually in the BIOS after replacing the battery (best option) or connect the computer to the internet and wait until Windows loads the correct date from a time server.

You could also update the time/date manually as soon as Windows starts.

Some programs throw up errors when the date reverts back to some distant time, several years ago in the past, when the CR2023 battery dies.

If you're lucky, when you buy a brand new (high quality) PSU, your computer will still work. Fingers crossed. If you're unlucky, you might have to replace the motherboard, if the Aresgame has destroyed it.

There are numerous "PSU Tier Lists" but try this one:
https://cultists.network/140/psu-tier-list/

If you choose something in Tier A (High-end), Tier B (Mid-range) or Tier C (Low-end) you stand a good chance of getting a decent PSU.

Please don't buy anything in Tier E (Avoid) or Tier F (Replace Immediately). It's just asking for more trouble.

How do I determine what size PS I need?
Provide us with a complete list of your PC components. Then we can advise on a new PSU.

At the very least we need to know the exact model (part numbers) of the CPU, motherboard and GPU card (if fitted). The motherboard part number is usually printed somewhere near the PCIe slots (up in the corner).

For a low end PC, another (good quality) 650W PSU should be fine. For a more powerful PC, you might need 750W or higher, but if your existing system has been running on a flaky Aresgame 650W PSU, I doubt it pulls more than 250W.

Good luck.