Thermal take PSU stopped working! Low 5v reading

luismenendez · 19 Mar 2019 at 12:59

Hi all,

I have a fairly old thermal take psu semimodular 700w which stopped working after going away for a week and switching off my pc from the mains. When I got back and switched the mains back on and my 8 years old pc didn't boot and not sign of activity. I thought it was the mobo and replaced the battery. I plugged and old 400w psu and pc working ok using onboard graphics. I tried the paper clip test on the PSU and seems fine. I bought a cheap PSU tester which I received today and there is low reading of 4.5v for the 5v which seems to be the problem because is making the tester to bip. The rest of the voltage are good.

My question is what components and lead are using the 5v?

Do I need to replace the PSU or any work around?

PSU runs a phenom II 4 cores @ 3200 (phenom 550 unlocked susessful to 4 cores) and ATI 6870 on a asrock 790x.

Thanks

Kelt · 19 Mar 2019 at 15:01

luismenendez said:
Hi all,

I have a fairly old thermal take psu semimodular 700w which stopped working after going away for a week and switching off my pc from the mains. When I got back and switched the mains back on and my 8 years old pc didn't boot and not sign of activity. I thought it was the mobo and replaced the battery. I plugged and old 400w psu and pc working ok using onboard graphics. I tried the paper clip test on the PSU and seems fine. I bought a cheap PSU tester which I received today and.there is not reading for the 3.3v which seems to be the problem as the rest of the voltage are good.

My question is what components and lead are using the 3.3v?

Do I need to replace the PSU or any work around?

PSU runs a phenom II 4 cores @ 3200 (phenom 550 unlocked susessful to 4 cores) and ATI 6870 on a asrock 790x.

Thanks

A quick Google tells me that 3.3V is used for at least PCIe and USB, so no workaround.

New PSU time.

luismenendez · 19 Mar 2019 at 15:09

Kelt said:
A quick Google tells me that 3.3V is used for at least PCIe and USB, so no workaround.

New PSU time.

Sorry, the problem seems to be a low 5v voltage (updated post)

Being using the tester for only 30 minutes so didnt understand it well

Kelt · 19 Mar 2019 at 15:12

luismenendez said:
Sorry, the problem seems to be a low 5v voltage (updated post)

Being using the tester for only 30 minutes so didnt understand it well

Still the same answer.

These things don't get put into PSU's for the fun of it

EsaT · 19 Mar 2019 at 15:39

Sounds like failed capacitors cooled permanently when disconnected from power.
Which is nothing that unexpectable, because Thermaltake has had relatively few quality PSUs, but lots of mediocrities and some marketing scam PSUs.

And I suspect it's 5V standby which is going haywire.
That's needed for motherboard's control electronics to be able to short/pull PS_ON wire down to ground when you press button of the case.
(same as what you do with that paper clip)
Though also other rails are possibly spewing out of ATX specification ripple at this point.

650W PSU would be plenty for those parts.
Antec Earthwatts is starting point for semi-modular PSUs with quality components.
https://www.overclockers.co.uk/search?sSearch=antec+earthwatts

HCG Gold or Seasonic Focus Plus next step for fully modular design.
https://www.overclockers.co.uk/search?sSearch=antec+hcg+gold
https://www.overclockers.co.uk/sear...ld/sPerPage/12/sFilter_category/PC+Components

Kelt said:
A quick Google tells me that 3.3V is used for at least PCIe and USB, so no workaround.

Then Google lies: USB uses exclusively 5 volts.

Kelt · 19 Mar 2019 at 17:21

It didn't lie...I misread it!

"PCIe is 3.3V, USB and ISA is 5V."

luismenendez · 20 Mar 2019 at 01:14

Thanks guys. It is a shame a have to bin the PSU as the other rails give good readings.

What do you think about getting a one-year-old Corsair RM 1000x from a mining ring for 70 quid without the original invoice?

cheers, Luis

Kelt · 20 Mar 2019 at 10:24

luismenendez said:
Thanks guys. It is a shame a have to bin the PSU as the other rails give good readings.

What do you think about getting a one-year-old Corsair RM 1000x from a mining ring for 70 quid without the original invoice?

cheers, Luis

I'd say that was a reasonable buy, but I'd want some warranty.

EsaT · 20 Mar 2019 at 17:11

luismenendez said:
It is a shame a have to bin the PSU as the other rails give good readings.

What do you think about getting a one-year-old Corsair RM 1000x from a mining ring for 70 quid without the original invoice?

DC voltage doesn't mean anything, if ripple isn't inside specification.
Which is something those "PSU testers" have no clue about.
Most of them can't even load PSU in any real way.
So they're worser for finding out PSU's load powering ability than using multimeter to check 12V (which is the most heavily stressed rail) and 5V from Molex of PSU when it's running PC.
And oscilloscope is only reliable tool for measuring PSU's condition, because even the best multimeters could only give at most vague hints about ripple.

Corsair might give some warranty just basing on serial number, but would certainly be good to have something better than assumption.

Kelt said:
"PCIe is 3.3V, USB and ISA is 5V."

PCIe has more pins for 12V than 3.3V, which is used by low power components.

luismenendez · 21 Mar 2019 at 00:22

thanks guys, I appreciate your input

Sasahara · 21 Mar 2019 at 01:07

luismenendez said:
Thanks guys. It is a shame a have to bin the PSU as the other rails give good readings.

What do you think about getting a one-year-old Corsair RM 1000x from a mining ring for 70 quid without the original invoice?

cheers, Luis

Warrantee isn't transferable, but it might be possible to wing it if the seller know the retailer it came from.

Though you just have to deicide if it's worth the risk. Given that it's run for a year on a mining rig suggests it's in good order. As it has a 10 year warrantee when sold that tell you the fail rate must be pretty low or Corsair wouldn't be able to do this.

I've had one of these on a mining rig for 2 years, been a solid performer. It's now on my test bench (Better PC than my main PC).