Old HX1000w PSU - Which 12V rails are the hardwired 12V PSU and 6+2PCIe cables attached to?

[bubo]

I have the old HX1000w psu, the one with the blue logo on the side, and am looking to keep this as I upgrade my current PC to a Z690+RTX3080, from current x99+GTX980ti. As I understand it the HW1000w is basically two PSUs in one, with the 12V output split into two rails, each with 500W total each. With a view to balancing the 12V load when I upgrade I want to know which of the two rails the hard wired 12V EPS 8pin mobo cable, and the 2x 6+2 pin PCIe cables are wired into on the psu.

I would imagine that the 2 gpu cables would would be split on to the two rails so the load would be split between the two rails as that would make most sense, but can someone confirm? The 12v mobo EPS cable I guess would be internally split as well? Or, are these all these cables biased to one of the rails, and you are expected to use the other rail for any extra PCIe and mobo EPS power?

With the RTX3080 I would not be using any of the modular outputs on the psu anyway, but I will be using one for the additional 8 pin EPS socket on newer mobos, would want to know if this should be on 12V1 or 12V2 on the modular modular connection.

It would be a shame to write this PSU off as it has served me well over the years and I get no coil wine with it at all. I actually already have the 3080 plugged into it with the x99 mobo and it seems fine. I accept that if I ever went to the RTX4000/5000 cards in the future that I would probably have to bite the bullet with a new psu, but for now I would like this psu to get one last hurrah.

 

tldr: Which of the two 12v rails are the hardwired 12vEPS and PCIe cables wired into on the HX1000w psu?

[LeDoyen]

I don't know for your request but it's usually adviseable to just get a new PSU when yours is this old. that's like a 13 - 14 years old unit by now depending on when you purchased it and the ripple filtering must be.. symbolic, given how old the caps are.

Pushing the current draw higher will just make it worse so it's very possible you'll stress the GPU and motherboard VRM because of it, or start experience crashes because the power delivery is too unstable.

[bubo]

Thanks for your reply, I was kind of expecting this to be the recommendation, I did ask a similar question on another forum and a replacement psu was the first suggestion there too given its age (2009). So am currently flipping between keeping it and replacing it with a RM850x. I suppose its because I don't know whether with psu's there is a point where it just falls off a cliff in terms of reliability, or whether it is a gradual decline after a certain point, which is making me hope it would just be ok given it seems to work as is with the 3080 and a 5820k clocked to 4.4ghz. That and wanting to save a few quid of course.

[LeDoyen]

they don't fail catastrophically like something blowing up inside or just not turning on.

You usually change them preventively with age because the capacitors age and filtering becomes a problem.

With DC voltage being rippled, the components VRM (motherboard, GPU) have to work harder to keep a stable voltage down the line.

So usually a bad PSU will kill components slowly, even if it itself seems to work fine.

So yes, the recomendation is usually to advise you to pay an extra 100 - 150$ to save your expensive CPU and GPU