PSU Load Testing

[mc605700]

I've been having stability problems with my computer for a little while mostly reboots without warning that seem to happen when I start up a graphically intensive program like a game. I suspect the problem is the power supply so I bought this:

https://www.amazon.com/HDE-Power-Supply-Tester-PCI/dp/B005UZHB6G

The power supply tests fine with this tester but I plugged the tester into a known bad PSU and it reads as if the bad supply is good. Everything in range. This makes me think the PSU's are bad under load. I'm wondering if it might be possible to test the PSU under load by getting a 24pin Y and an EPS12v Y and plugging them into the tester while the system is running. That way I could watch the voltage under various use patterns directly without having to rely on software.

I assume I will have to cut out the Pin 14 power-on as I won't need the motherboard and tester both shorting it.

Is there some reason this wouldn't work?

Thanks!

 

[Aeacus]

That little PSU tester doesn't put any load to the PSU. Instead, it reads the voltage levels of idle working PSU. With that tester, every PSU passes that can keep safe voltages under no load.

For you, the issue is when there's load put on the PSU. Most low build quality PSUs fail to deliver their marketed wattage or fail to keep safe voltage levels once there's a load put on PSU. Hence the random reboots you're experiencing.

What's your full system specs, especially PSU make and model (or part number)?

 

[mc605700]

I know the tester doesn't put a load on. That's why I want to know if the Y's will cause a problem so I can run the tester on the line while the system is loaded. The PSU is a Seasonic G series 750w that's about 5 years old. The system is a Core i7 4470K with a R9 280x. It ran stable for years it's just become unstable in the past year. I am guessing it's the PSU but I want to be sure it's not the Mobo and I don't have a spare supply to sub in or the funds to mess around buying replacement parts till I figure it out.

Will putting at Y on the 24pin connector and the EPS 12v connector and then connecting the tester to the system in this way be a problem?

I don't imagine that it would be but I don't know enough about how the circuits work to tell for sure and I don't want to blow up my system by accident as I can't afford to replace it.

 

[Aeacus]

There's no way you can put the tester between PSU and working system since all ports that tester has are input ports and there are no output ports. Wiring it any other way than it is intended may fry the tester and your system as well. Also, i don't think the tester is designed to handle a 400W or so load. Even 100W load could fry it.

As far as Seasonic G-750 goes, it's good quality PSU. But since it came with 5 years of warranty and that has expired now, it's safe to assume that PSU is slowly dying. Hence the issues with PSU. Though, Seasonic PSUs are one of the few on the market who usually last far longer than the warranty given to them, but that's not always true.

Here, i suggest that you get yourself a new PSU, in 600W range. Your R9 280x is 250W GPU, add the rest of the system at 200W or so to it and max power consumption you're looking at would be 450W, making 650W PSU more than enough.
That being said, you can go for any Seasonic PSU in 600W range, e.g: Focus 650 80+ Gold, Focus+ 650 80+ Gold, PRIME 650 80+ Platinum or PRIME 650 80+ Titanium,
pcpp: https://pcpartpicker.com/products/compare/nn648d,pHFXsY,WrNypg,qn7v6h/

Focus and Focus+ are the newest PSU lines from Seasonic and they come with 10 years of OEM warranty. While PRIME series PSUs are the best offered by Seasonic and they come with 12 years of OEM warranty.

Also, PRIME 650 80+ Titanium is the best 650W PSU money can buy at current date and with it, you'll get the highest efficiency (94%), tightest voltage regulation (0.5%), longest hold-up time (30ms), lowest ripple noise (20mV) and longest warranty (12 years) there is. Fully modular cables and toggle-able Premium Hybrid fan control too.
specs: https://seasonic.com/prime-titanium
review: http://www.tomshardware.com/reviews/seasonic-prime-titanium-650w-psu,4690.html

All my 3 PCs: Skylake, Haswell and AMD are also powered by Seasonic while i have the PRIME 650 80+ Titanium unit in Skylake build. Full specs with pics in my sig.