Power supply too small?

S

SultanGris

Limp Gawd
Joined
May 14, 2006
Messages
330
Whenever my power goes out and my computer is on when i press the button to turn it back on the lights on the case flash for a sec and the fan starts and then all power cuts like its tripping a breaker or doesnt have enough juice to start or something. if i clear the cmos it fires right up but this is less than ideal and a huge PITA cause my power goes out quite frequently and i have lots of settings tinkered with. Sometimes if i hold the button it will flash starting and stopping a few times and then take off but i dont recall it ever doing this before and its not normal.

I have a coarsair HX620W PSU and my system specs are thusly,

Asus p6t,
Intel core i7 920 @2.67ghz
Radeon HD6900,
Soundblaster audigy 2 zs,
6gig ddr3
2 sata drives 250gb and 750gb, 1 SSD 500 samsung evo and one IDE 80 gig i was testing out but currently unplugged from power as it was making an odd noise.
1IDE DVD burner and 1Sata blueray drive
3 little case fans with blue led lights on them and one large case fan
Windows 7

originally built a few years ago with a NVIDIA 8800 gts but upgraded to the radeon a year ago which may have been my issue, it has two IDE style power connections that i have running on their own cord from the PSU with only that and one little case fan each. Cant remember if it did this with the previous video card or not but it doesnt have any issues while its running so im not sure if its a power supply issue or something else, any thoughts would be appreciated, thanks.
 
Which 6900 do you have? If it's the 6950 or 6970, the power supply should be more than sufficient for your system. And if you have frequent power outages, get a UPS. That issue sounds more like a motherboard issue than a power supply issue, and clearing the CMOS would have nothing to do with power.
 
My guess is that 3 are the "suspects" for your problem:
PSU, GPU, mobo
In order to take the mobo out of the suspect list, i would suggest to take out the GPU, and use the onboard gpu. If everything works fine, we can assume the the mobo is not the problem and focus only on GPU, PSU.
After that, you can borrow from a friend either a PSU or a GPU, whichever is available, and find out what causes the problem. ;)
 
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My bad, its the 6970. Also i should point out that there is no issue if i shut it down and turn it back on, this problem only occurs after loss of power while its on for some reason, and as i said CMOS clearing isnt required, but it does work effectively. If i simply hold the button it will attempt to power and fail 4-5 times and then correctly power with no loss of CMOS settings but its like the power isnt enough to kick it over fast enough to fully engage it or something, lol, not sure but i wouldnt think that is very good for it so i use the CMOS clearing method instead. Doesnt make any sense too me.
 
Any difference if you flip the power switch on the back of the power supply?
 
if i do so when its turned off properly via using shutdown from the start menu and wait till the power bleeds out completely and then turn it back on it has no issue, if its lost power while turned on and i turn the switch off while the problem exists and the machine is not running then there is no effect, and the problem still exists.

I dont remember exactly when it started happening which makes it hard to determine the cause because it didnt used to happen too frequently but recently weve had some storms that have caused it to go off more than normal and its become annoying cause my tower is in my desk slot and all my cords are too short to pull it out far enough to access the motherboard without sticking my arm through a very small opening trying to find the right spot to plug things in without being able to see them :D Im not much of a believer in UPS as they are very expensive and dont offer much time to shut down manually in the first place and over time the battery degrades so fast it gets shorter and shorter and many of my power losses occur when im not home so it wouldnt really be of any benefit to me unless theyve gotten smart enough to detect power loss and trigger an automatic save and shutdown, lol! Plus ive lost power hundreds of times in the last 20 years and nothing hardware wise has ever been damaged as a result anyway. maybe it would be useful if i was typing important documents nonstop but most of those auto save now anyway so i really see zero benefit at all. If it would last 10 hours in the event of an extended outage i might consider it worthwhile, heh.
 
Again, sounds like motherboard issue, although there is a remote chance it can be a PSU issue as well (highly unlikely).

Best fix for your scenario is to get a UPS. Prevents data loss, and lengthens life expectancy due to proper shutdown sequences. And there are plenty of high capacity UPS out there, that have been proven reliable. Your thoughts on avoiding UPS are irrational at best. And with modern UPS, you can connect them to your computer with a USB cord, and your computer will act like it's a laptop, configurable with automatic shutdown or hibernation once battery percentage reaches a certain level.

Plus, with unstable power, your power supply may not be getting clean power, forcing it to work harder and shorten its lifespan. A good UPS will ensure clean power to your power supply.
 
that might make them mildly useful, they couldnt do that the last time i was checking them out and therefore were 100% useless to me as most outages occur while im away. ill check into them, thanks.
 
Since i ran into a very similar situation my guess is leaning on the motherboard since we both have almost the same boards....i also noticed the only fix was a proper clear cmos, reset defaults, then re did bios settings......thing is mine did it without a power outage as far as i know....but i cant be certain come to think of it......the only thing in common is we both running asus x58 boards so to me it appears to be related to our boards in some way

took me all day to think of resetting the cmos when it happened lol cause i really thought my power supply died or something lol yea kinda silly looking back;)
edit: if your power is going out really that often i would be looking into getting a ups if you could afford it.......i cant imagine a lot of power losses being very nice on an os
 
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primetime said:
Since i ran into a very similar situation my guess is leaning on the motherboard since we both have almost the same boards....i also noticed the only fix was a proper clear cmos, reset defaults, then re did bios settings......thing is mine did it without a power outage as far as i know....but i cant be certain come to think of it......the only thing in common is we both running asus x58 boards so to me it appears to be related to our boards in some way

took me all day to think of resetting the cmos when it happened lol cause i really thought my power supply died or something lol yea kinda silly looking back;)
edit: if your power is going out really that often i would be looking into getting a ups if you could afford it.......i cant imagine a lot of power losses being very nice on an os
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its strange, thats the only time it happens, and yea, first time it took me while to figure it out too, i was like WTF?? lol, but it works 100% with no issues any other time, so im pretty skeptical its the board. a setting maybe, but id excpect to see issues at other times as well, or even when i shut it off manually if it was the board in my opinion, but im no expert.

What sort of OS issues could there be? in 20 years of computing ive never had a single issue related to power loss other than the text i was typing at the time of occurrence gets lost, lol! I can think of much better things to spend money on than a UPS. Maybe Ill get one when they can develop a battery that lasts longer both when being used and stay at that quality 5 years later and not end up with a 10% of original working ability after a few years like current battery technology.
 
Get a UPS. /thread

You don't want to do that, we can't help you any further.
 
Tsumi said:
Get a UPS. /thread

You don't want to do that, we can't help you any further.
Click to expand...

I tend to agree...if your having frequent power outages then a ups is very practical...otherwise at least you know how to fix it every time it happens:)
 
fair enough, I was more looking for the root cause or a logical reason why this happens rather than trying to prevent it from happening however, but thanks anyway.
 
I already gave you my suspicions for a root cause, with it being a motherboard problem.
 
I dont understand how it only happens when the power goes out if there is something wrong with the motherboard though, and after more testing ive found if i simply hold the power button after it happens it will flash on/off for a second like 5 or so times and then fire up fine every time, very strange, lol
 
Don't try to understand it, electronics, particularly computers, are very complex and sometimes finicky stuff. The power supply only understands one thing from the motherboard, and that is the power on signal. If it doesn't receive the power on signal, it won't turn on.
 
I suspect some ASUS motherboards have some kind of fail-safe built-in that will prevent them from powering on immediately following a power loss event. The P8Z77-V LK that I have does this. I have to shut off the power supply, wait for the on-board LEDs to go out, then I can power it back up without issue. Either that or it is a bad motherboard (it does have a host of other issues, mostly BIOS related) and I've just been assuming that it was a built-in fail-safe. :confused:
 
MrCaffeineX said:
I suspect some ASUS motherboards have some kind of fail-safe built-in that will prevent them from powering on immediately following a power loss event. The P8Z77-V LK that I have does this. I have to shut off the power supply, wait for the on-board LEDs to go out, then I can power it back up without issue. Either that or it is a bad motherboard (it does have a host of other issues, mostly BIOS related) and I've just been assuming that it was a built-in fail-safe. :confused:
Click to expand...

I think most boards have some sort of power loss setting in the power management settings somewhere
 
Draconian said:
I think most boards have some sort of power loss setting in the power management settings somewhere
Click to expand...

Yes, but that only controls whether the computer should automatically turn back on after power loss or not. It is not relevant to this issue.
 
Looks like a motherboard issue but as everyone else said get yourself a UPS, can easily find one on sale this time of the year.
 
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