SMPS or UPS Problem..?

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petes

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Need some opinion on the following issue. I have the following configuration:

Intel Pentium Dual Core, 3.2 Ghz
3GB DDR2 800Mhz Ram
500GB+250GB Hardisk
Nvidia XFX 8400 Graphics Card

SMPS: Intex 450W
UPS: APC 650 VA

Problem: Occasionally, my computer restarts on Power failure. However, nowadays it is happening very frequently. This problem persist from last 5 to 6months.

There is a series of communication happening with APC from last 5 to 6 months, but till this date, no solution has been provided. Many times they have taken my UPS to the service station but still could not rectify the problem. Most of them blame SMPS is causing the problem. But still i am not convinced with this reason.

Any idea how to check whether the problem is really related to SMPS or UPS??

Thanks!!
 
Try changing each of those.. you'll figure out.. :) n if problem is not with either of them then start replacin other parts like key or mouse.. i remember once i was having same problem.. n after strugglin for few days i came to know that problem is with keyboard.. i changed it n i never had any problem with system restart..
 
One good way to find out is to beg/borrow/steal another UPS from a friend and see if the problem persists. As the APC people pointed out, the problem could be the SMPS also. Best bet is to borrow another UPS and see. If the problem persists even with another UPS then it is most probably the SMPS.
 
If it is a SMPS problem, then why should the computer restart only when power failure? ;)
Am not ruling out the SMPS. Just curious to know how it could be.
 
Well a faulty SMPS could be causing the computer to restart during power failure owing to the fluctuation.
 
Connect the UPS to another device and see if it suffers the same fate too... like perhaps a TV/ speaker system
 
hi all,

I have a similiar issue. There is serious voltage fluctuation at my place. My computer is connected to a vguard 700va ups on a inverter line powered by apc 1000va. Sometimes when there is contious fluctuation which i can understand from the redlight of ups, my system gets restarted. It doesnt happen all the time. I feel it has something to do with the lag b/w ups and inverter on power failure or low/voltage cutoff. Has anyone similiar setup or faced similiar issue. I cant refer this to vguard since i dont know when this will happen. Will it be an issue of smps for me also.
Sorry pete for raising another query in your thread. i think i have a similiar issue as yours.
Thanks,
Antony
 
@Petes -I suggest you to change your SMPS. The restarting may be due to the SMPS not capable of giving the necessary power during the UPS switch over time. Your system with such a dedicated GPU needs better PSU. Consider good quality 500W SMPS from Cooler Master, Corsair etc.

@az2325 - My place also had this frequent voltage fluctuations. Instead of the current offline UPS, buy a line interactive UPS. Unlike offline ups, these have automatic voltage regulator 140V - 270V. I am using one and now there is no more switching back and forth between battery and mains. This increases battery backup time also.
 
Is your UPS connected to a power outlet that gets inverter backup? I've experienced issues similar to the one you've described when my UPS was so connected. If you change the power outlet to one that does not get inverter backup, this problem might get solved.

I'd also suggest that the SMPS be changed, regardless of whether the problem is the one I've mentioned above. Your setup will benefit from a better SMPS, and you will also benefit from lower power consumption, if you shift to a good quality 80plus rated SMPS of one of the brands baijuxavior has mentioned above.
 
I would say its because you have connected both monitor and CPU to the UPS and for sure if there is power failure, your PC will get turned off, to check this, connect you monitor directly to the power outlet, so the next time power goes off, your CPU wont turn off or restart.
 
it has to be the UPS:

as mentioned yes it cna be due to keyboard too. i had that issue but why only when power failure: ruled out

smps : why restart only at power failure rest time system is all good : ruled out

ups: yes

why : the lag between the ups battery powering up the pc :

tried and tested : pc apc ups : power fluctuates: pc still on
4 yr old wipo ups : xternal HDD restarts:

it has to be the UPS... try borrowing one from a friend and that should isolate it..
another reason.. 600 va as you mentioned
would pump out around 400 watts.. now if you running the pc as well as monitor on the same due to load it is supposed to happen

so even if the the UPS is fine but overloaded this is pretty normal behaviour...
 
Thanks all..I would try all the remedy mentioned by you and will update on that.... actually, the moment i posted this thread, UPS or SMPS is now steady and did not restart on power failure, this happened twice since last few days...

This problem ocurrs only when there is a power failure (that too occasionally) and not when there is a power... I read somewhere that, one reason for SMPS problem is that, the system would restart intermittently even when there is power... still not sure

Anyways, I will observe for few more days and I am thinking of changing the SMPS to CoolerMaster or the one that is suggested in this thread irrespective of problem exists or not...

I also wanted add that, my UPS is NOT connected through home inverter (it has a separate line)
 
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BalaHiFi said:
I would say its because you have connected both monitor and CPU to the UPS and for sure if there is power failure, your PC will get turned off, to check this, connect you monitor directly to the power outlet, so the next time power goes off, your CPU wont turn off or restart.
Click to expand...
It is the total load that matters. My APC supports PC, monitor, table lamp, modem, router (and powered monitor speakers too, if I want) ... for over two hours. It is at only 13% of the UPS permitted load. This can always be checked with the APC software (and, for linux, gapcmon).

You wouldn't be able to use the computer if the monitor was not attached to the UPS! That wouldn't be much good :cool:
 
Thad E Ginathom said:
It is the total load that matters. My APC supports PC, monitor, table lamp, modem, router (and powered monitor speakers too, if I want) ... for over two hours. It is at only 13% of the UPS permitted load. This can always be checked with the APC software (and, for linux, gapcmon).
:
Click to expand...



ups supports all that for 2 hours ?? is it a pc ups ??

the one he mentioned is a 600 va ups that will hardly support a 400 w pc for 20 min max..
 
Yes... but only an example. I used to use an APC Back-UPS500.

The machine may have a 450w PSU: it doesn't mean it is drawing 450w. Mine is over 800w, but the total load on my UPS, most of the time, is around 112w for all the connected equipment. Using the APC Powerchute software, along with the USB connection, allows this to be monitored easily, along with how long the UPS is capable of powering the connected gear.

The time factor is just a matter of scale, according to model. But yes, as my teachers used to tell: I didn't read the question properly :eek:
 
Thad E Ginathom said:
Yes... but only an example. I used to use an APC Back-UPS500.

The machine may have a 450w PSU: it doesn't mean it is drawing 450w. Mine is over 800w, but the total load on my UPS, most of the time, is around 112w for all the connected equipment. Using the APC Powerchute software, along with the USB connection, allows this to be monitored easily, along with how long the UPS is capable of powering the connected gear.

The time factor is just a matter of scale, according to model. But yes, as my teachers used to tell: I didn't read the question properly :eek:
Click to expand...

the one that you have does have a usb cable seperately that can be used with windows ups managemt
however the 600 va is the basic model that i had too and does not have anything to identify load from pc.

i also completely agree that pc does not run over full power all the time but with time various factors come into play in the UPS..

battery condition..
also there is a cutout voltage for every ups / invertor .. till that time the UPS wil not come into play.. now in his particular scenario the voltage might just be dropping a bit and then going off and that probably fooling the UPS.. so while the voltage drops to a level where the UPS acts the pc already reboots..

new UPS are sensitive though.

my old wipro UPS. keeps the PC on but the external HDD goes off and on..
 
My 500 is nearly six years old has a USB cable: I expected the 600 would. Wrong again it seems. But APC had this nasty habit of using an RJ45 connection at the UPS end of the USB, which can mislead. Oddly, some of the higher-range APC units do not have USB (some of them have odd things [these days] like serial ports).

The 500 did a very good job of supporting a laptop +modem +lamp. Even when the laptop battery was out and contributing almost nothing. When it came to a desk-side, with a CRT Monitor, it was reduced to a few minutes. But it always worked. The PC always marched on regardless.

When I upgraded to a much bigger UPS, I used the 500 for the hifi. Guess what? It will power a PC through its switching time --- but not my Cyrus Amp! Indeed, different things have different sensitivities.

Since my last battery change, I have been having some inconveniences: the voltage output must be changing when the UPS switches in. The LCD screen flickers, and sometimes even blanks for a moment or two --- but the PC never stops. I guess I should get it checked.
 
After observing for a week, this is the trend what i have noticed.

System will not restart and works fine in the battery mode when there is a power failure within first half an hour of switching on the computer.... However, after half an hour or 45 mins, if again there is a power failure, the system is restarting and does not pick up the battery mode....

After consulting with one of my friend (computer technician), he said that, this problem could be due to heating of Diode (related to some time delay) which is found at the back of the cabinet (may in Motherboard, not sure..). Since the diode will need some time to get heated, computer is not restarting during first half hour and later, once it gets heated computer restarts..

Anyone have idea about this diode or is it something not related to the problem..?

FYI... My UPS is APC 650 VA and the load as per powercute software will be around 140 W.
 
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petes said:
Need some opinion on the following issue. I have the following configuration:

Intel Pentium Dual Core, 3.2 Ghz
3GB DDR2 800Mhz Ram
500GB+250GB Hardisk
Nvidia XFX 8400 Graphics Card

SMPS: Intex 450W
UPS: APC 650 VA

Problem: Occasionally, my computer restarts on Power failure. However, nowadays it is happening very frequently. This problem persist from last 5 to 6months.

There is a series of communication happening with APC from last 5 to 6 months, but till this date, no solution has been provided. Many times they have taken my UPS to the service station but still could not rectify the problem. Most of them blame SMPS is causing the problem. But still i am not convinced with this reason.

Any idea how to check whether the problem is really related to SMPS or UPS??

Thanks!!
Click to expand...

Sorry for the late reply, as I came across your post today. Well I can guarantee its 100% SMPS responsible for it. Reason- I had been grossly disturbed with this trouble since past 3-4 years. By the time I forgot that I had replaced my SMPS which got fried due to power surge. After changing the smps (earlier) I started facing this "Occasional" issues. I tried everything what others have mentioned. Even did many other experiments. Like in my case when I disconnected the power from the changeover switch the UPS functioned well. But when there was a power cut it used to trip occasionally. Finally i reached to this conclusion that the culprit was the SMPS !! which was confusing the UPS. I have 3 UPS at my place tried all of them and the results were same. So SMPS was the real cause.
 
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