VOLTS +3.3v +5v +12v

[kev8792]

sorry if this is in the wrong place,

my question here for help is with the folling picture




as you can see the +3.3v isn't quite near 3.3v and neither is the +5v

about 3 months ago they were a lot worse the +5v was around 3v and the +3.3v was around 2v my o/c was unstable that's the first signs i noticed and it came down to a cheep 24pin extension wire from ebay (i know me bad ;-) ) so i got rid of that and now have no extension wires, just strait from psu to components

could someone please help and maybe upload what your readings are

many thanks guys

[parsec]

Re: VOLTS +3.3v +5v +12v

Your link to the picture is not working, so I have no idea what you are using to check the PSU values, or the values themselves.

These are mine as shown in the BIOS:



The standard range for the 5V supply to be in ATX spec is: +4.75 V to +5.25 V.

The standard range for the 3.3V supply to be in ATX spec is: +3.135 V to +3.465 V

Both of those ranges are +/- 5%.

[kev8792]

Re: VOLTS +3.3v +5v +12v

thanks Persec, sorry about the image not working i'll try it again and i should have said im using HWINFO64 to read the volts in windows as they read the same as in bios



i hope this works this time.

from what you said above it would seam i am within the margins though only just as right now my +3.3v is @3.168v the + 5v isn't as bad reading now @4.983v

[- wardog -]

Re: VOLTS +3.3v +5v +12v

Those readings are rather stable and don't look like the system been placed under a load yet, have they?

[kev8792]

Re: VOLTS +3.3v +5v +12v

no that was just idle, this is under load running prime95 and tonight my +3.3v is even lower again

[- wardog -]

Re: VOLTS +3.3v +5v +12v

Both pics don't look good for your PSU's 3.3v line. Neither come close to an actual 3.3v. And under load, 3.088v, looks lousy as that is clearly out of spec.

Are you still experiencing stability issues with it like this, now sans the cheap ATX extender?

[- wardog -]

Re: VOLTS +3.3v +5v +12v

Open my eyes some and that 5v line at 4.785v while loaded is JUST hanging in there only by one or two whiskers.

[kev8792]

Re: VOLTS +3.3v +5v +12v

Thanks wardog, im glad you noticed there is something wrong, i thought it was just me going mad.
the system stays stable like i can play any game at max settings without any issues "BUT" if i run intel burn it will BSOD so not stable at full load

this morning i have disabled all led's and al fans = still got the same volts as in the last picture above,
i have tested the PSU with a PSU tester and all seams fine, the +3.3v and +5v all say what they should say so i don't think its the actual PSU but now im at a lose as to what i can do, thanks for your reply's

[- wardog -]

Re: VOLTS +3.3v +5v +12v

i have tested the PSU with a PSU tester and all seams fine, the +3.3v and +5v all say what they should say so i don't think its the actual PSU but now im at a lose as to what i can do, thanks for your reply's

I'd say to borrow someones spare PSU, one big enough to power your system!, and see what those +3.3 and +5 voltages look like idle and loaded when you do place it in there. That'd be the easiest way around "now im at a lose as to what i can do". And it's sure less work than any of the other alternatives I can think of.

That or, and I don't like suggesting folks buy to test and then return, if a local brick and mortar or e-tailer with a liberal return policy has a PSU you might have your eyes on for this system, buy it, install it, and see what she does voltage wise with a new heart powering her.

[kev8792]

Re: VOLTS +3.3v +5v +12v

thanks again wardog

unfortunately i don't have a spair psu nore have the money to buy and try tho very nice idea, iv just had the 24 pin wire off and blown out the 24pin socket, put it back together and pushed each wire in with a small screw driver just incase its a loose of faulty conection, and this is what happened, the first picture is idle the second full load wit prime95



as you can see they are better but still not quite right on the mark as they should be

[- wardog -]

Re: VOLTS +3.3v +5v +12v

Those look better. I could live with those numbers if I had to/for the time being. As long as it's stable.

re: IBT I read somewhere that IBT was the absolute worst thing you could make a CPU endure. They, multiple peoples posts, referred to it as totally unnecessary and even harmful to the CPU. Is that still some peoples consensus of it?

[kev8792]

Re: VOLTS +3.3v +5v +12v

yes i think i will stay away from ibt for now and just use prime95, does anyone know what actually runs on the 3.3v rail ? or does it depend on what mother board im using, if i knew what ran on the 3.3v maybe i could narrow it down to something, i don't think it would be the psu its self as that's tested fine on the psu tester, al lights were green, tho id rather i had a digital psu tester

[- wardog -]

Re: VOLTS +3.3v +5v +12v

Meh, don't go giving the PSU tester results too much weight. The load tester is your configured system, not any hand-held PSU tester thats basically a go/no-go checker.

I believe, I say believe, on this board 3.3 powers the memory. I may be wrong there though.

[parsec]

Re: VOLTS +3.3v +5v +12v

In the past, the 3.3V and 5V rails were used by the CPU, but that was changed quite a while ago. Now the 12V rail is used to provide power to the CPU, indirectly through the CPU's VRMs. The 3.3V and 5V rails are not used much by the board itself anymore, but still should be within spec. HDDs are provided with all three voltages, although some may not use the 3.3V rail. 99.999% of SSDs only use the 5V rail. The amount of power drives use is low compared to the CPU and video cards.

Your PSU is a bit odd IMO that the 3.3V and 5V rails seem to droop as much as they do, while the 12V rail is quite solid and consistent. That is the case while using a DC to DC conversion design for the 3.3V and 5V rails, meaning they are derived from the 12V rail and not from their own dedicated AC to DC circuitry. That design is found in the best current PSUs and is considered to be a superior design.

Found a good review of this PSU: Thermaltake Toughpower XT 775W Review

It received a good review, although the minor weak points included a somewhat low regulation on the 3.3V and 5V rails, but within ATX spec. It looks like the 12V rail was tweaked up a bit after the review found it to be a bit low at low load, yours at 12.4V+ is why I say that.

You might want to do what you did with the 24 pin cable to all the other cables. Meaning disconnect them and plug them in again and be sure the pins are all the way in as you did with the 24 pin cable, a great idea (which I do as much as possible.)

OTOH, age might be showing up now, as your PSU might be about four years old now? The parts in a PSU do suffer the affect of age over time, particularly the filter capacitors that are a main part of keeping voltages stable. Your voltages are not terrible now that you "fixed" things a bit, but I would also be bothered by those readings since they aren't perfect.

Do you use any extension cables in that PC? Or adapter cables of some kind? They could add resistance to the load the PSU "sees" and contribute to the voltage droop. Otherwise I don't see any strange or terrible loads on the PSU.

If your PC is stable and functions fine, I would not worry about this to much, but you might want to put a new PSU on your short list of future upgrades.

[kev8792]

Re: VOLTS +3.3v +5v +12v

thanks parsec, all the reading so far are without any extensions added, now i have bought all new extensions and this time a better brand, Silverstone, i installed the extensions and did what i wrote above, pushing every wire in with a very small screw driver, my readings changed, this time for a slight better reading, my +3.3v idle are now 3.296v and under lead 3.264v so much much better, my +5v idle 4.946v and loaded 4.865v the +12v is something iv never had any probs with reading 12.493v idle and 12.429v loaded.
i went and read the review from the link you gave above and i can see from there testing that im pretty much alright with these readings, i bought the psu brand new from Computer Hardware - Scan.co.uk just over a year ago

thanks for your time and help