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+3.3v is at +2.05v!

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February 1, 2007 2:35:36 AM

is this normal? the pc wizard is showing me this reading. and the bios reading on +3.3v is on fail. is it dangerous to even power it on, let alone play games?

More about : 05v

February 1, 2007 2:44:44 AM

Download speedfan and then see if those voltages can be confirmed.
February 1, 2007 2:48:11 AM

its still 2.05v. that is also the rating of the vcore2
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February 1, 2007 3:26:01 AM

well, it happened when i installed that tt dedicated psu for my vid cards. there is an adapter so that it will be on as soon as the computer is on and vice versa. ill try connecting it direct and il post again
February 1, 2007 3:55:09 AM

i connect it directly and its still like that. i know i just bought this psu recently, so i wish its the psu. i have exchanged and returned this mobo a number of times that im very uncomfortable even going there.
February 1, 2007 4:23:41 AM

yeah im still having it. and i bought the tt when i had a 400 watt power supply, and i put it in cause i thought it would reduce the stress of the main psu
February 1, 2007 4:33:27 AM

so should i get 700 watts or more? any recommendations?
fyi: i got this in a retail store of tiger direct at $165 CAD
February 1, 2007 4:45:17 AM

well, none of them is at the .ca site of tigerdirect, but ill try and get the same one considering its 18x2 on 12v rail
February 1, 2007 5:18:36 AM

whoah there, before you go blow money on a new psu, are you actually having any stability issues? lf your rails were actually that off, your computer wouldnt even turn on. those readings are software readings, so unless you go get a mutlimeter and actually measure the voltage, dont take heed of the software reading.
February 1, 2007 12:19:25 PM

Quote:
The +3.3V rail is what supplies the power to most of the chips on your motherboard. SO if those readings are correct then your CHipset is being under powered. This can lead to many problems in the system if left for too long. I would suggest getting a new PSU.


That's not entirely accurate, a few chips do use 3.3V directly but most of the higher tech stuff uses a lower voltage derived from a step-down circuit, with that supply rail merely having to remain above the inherant voltage drop + resultant voltage sum. If the system is running stabily it most certainly is above this threshold.

I'd wonder if the reading is even accurate though, IF the PSU is actually outputting that far below 3.3V it should have shut off already. Before further changes or parts replacement it would be prudent to use a multimeter to take a reading of 3.3V and 5V at the motherboard connector.
February 1, 2007 1:15:14 PM

You really need to check that PSU with a meter. It may be that the motherboard's onboard sensors have gone bad which could cause problems. Here is a guide on how to quickly check your voltages using a cheap meter like a $20 Radio Shack portable. It is very easy to do. http://asustech.15.forumer.com/index.php?showtopic=623
February 1, 2007 2:04:47 PM

Current motherboards usually convert 12V to Vcore and Vnoth_bridge. The reason is simple: 12V allows higher efficiency for the DC-to-DC regulators. The regulators themselves are powered off the 5V rail, but some can use the 12V rail also. I highly doubt any PC has regulators off 3.3V. PCI-Express has 3.3V and 12V (3.3V for logic level and 12V for power).

Most new motherboards look at PWR_OK and other signals directly from the PSU unit. If these are not within 10% of nominal, then your system will not boot.

In summary, if you're PC is up and running and does not BSOD or crash for you linux users, I highly doubt you have a voltage problem.

Another indicator would be a ton of hot air out of the PSU - the silver box will do everything it can to get that 3.3V up to at least 3.0V.

Also keep in mind that the silver box is designed to give the proper voltage under load - it is usually measured with a few Amps of current to make sure it is in regulation. If you plug in a PSU and measure no-load - do not be surprised if the voltages are all over the place.
February 1, 2007 2:39:47 PM

i tried another psu. as it turns out, its the mobo. i had stability issues when i load tons of app and vids then i saw the the reciever flashing meaning that mobo is having sound issues, onboard sound. after that, i shut it down and never used it since then in concern at potential catastrophic damage. thanks you all
February 1, 2007 6:07:30 PM

Quote:
Most Current motherboards usually convert 12V to Vcore and Vnoth_bridge. The reason is simple: 12V allows higher efficiency for the DC-to-DC regulators. The regulators themselves are powered off the 5V rail, but some can use the 12V rail also. I highly doubt any PC has regulators off 3.3V. PCI-Express has 3.3V and 12V (3.3V for logic level and 12V for power).


You can doubt if you like, but they do, particularly for memory. It is not very significant difference in efficiency using 12V for this purpose, while it is possible, it is just as viable to use another rail, particularly so the board isn't putting an undue burden on only one rail which tends to cause problems for "most" PSU because "most" don't have truely independent regulation.

Quote:
Most new motherboards look at PWR_OK and other signals directly from the PSU unit. If these are not within 10% of nominal, then your system will not boot.


That is overgeneralized unto the point of being incorrect. You can take some new boards and just short the PS-On and Gnd and get a board running even without Pwr-Ok connected.

Quote:
Another indicator would be a ton of hot air out of the PSU - the silver box will do everything it can to get that 3.3V up to at least 3.0V.


Absolutely NOT. For one, the 5V rail and with newer PSU, 12V rails are those weighted to obtain the regulation, the 3.3V is a derivative on most, and even with independent rails the 3.3V is not the priority feedback rail, the PSU will let that rail drop, but not down to 2V.

It would not create a ton of hot air either, this has no backing at all. If it only increased one rail on an independant rail system it would be a fairly trival increase in total power consumption, or if non-independant rails, there would be a corresponding increase in voltage on the 5V rail, IF the PSU had enough bias to 3.3V in the feedback loop, which the majority do not. No matter what happened (except for a failure) the condition would not suddenly start producing a lot more heat.

Quote:
Also keep in mind that the silver box is designed to give the proper voltage under load - it is usually measured with a few Amps of current to make sure it is in regulation. If you plug in a PSU and measure no-load - do not be surprised if the voltages are all over the place.


Here we agree.
February 1, 2007 11:42:47 PM

I wonder whats worse, mine is running at 4.03V! :?
February 2, 2007 2:28:36 AM

woah! can i borrow 1v?
February 3, 2007 11:50:27 AM

Quote:
I wonder whats worse, mine is running at 4.03V! :?


This is from a multimeter reading? If not, it would be good to get a confirmation.

This would usually be from a poorly designed PSU that had insufficient internal loading, and with a system that isn't using 3.3V rail, also the PSU doesn't have enough (if any) feedback on the 3.3V rail so it is what's called "floating" high.

It may not directly cause any problems if the system isn't using 3.3V at all, but is still a situation best avoided, as are PSU that would let this condition persist without shutting off. Any PSU is supposed to shut off by the time a rail exceeds the spec. It is often excusable on rails rarely used these days like -5, -12V, as they're such low current that having an internal load would just waste more power and lower the PSU efficiency that many in the industry are pushing to raise over 80%.
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