Discussion Power supply discussion and review list thread

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Something I feel that should be noted and highlighted now as it is important.

With the newer MB's a lot of them have 2X Power Connections.

Only the better 750W and above Modular PSU's have 2X CPU Power cables.


Seasonic Focus Plus, Prime Series
EVGA G2 and G3
Corsair RMX

Very few 650W and below units have 2X Power Cables, NONE of the budget units people seem to recommend have them.

I know the Seasonic X-650W and Seasonic 650W Prime Titanium have 2X CPU Power cables.


That is noteworthy, however, for the most part those additional CPU power connections are only needed for extreme/competitive overclocking. All of those boards will run perfectly fine with only the standard 8 pin (4+4) EPS connector, even on the 8/16 CPUs.

Until they don't, and we are already seeing it here on THG with the newer boards. Mainly the Z390 Boards, so it's something to watch for.

Reason why I brought it up.

I think the way the Z390 power systems is setup may be different on some boards, so they really do need both CPU power connections connected?

Rogue Leader




Thats the manual for the Maximus XI. If anything you'd expect that board to need it yet if you check out page 2-7 it says you can connect only the 8 pin, or do the 8 and the 4.

IMO if you're running a 9900k you'd be dumb not to connect it. But there is no requirement.


I think if you are overclocking to ANY degree on a board that has it, then you should use it. And if your power supply has it, and your board CAN use it, then use it. But if you are running at the stock configuration and your power supply does NOT have it, then I see no reason to worry about it as you're never going to draw more power than the single 8 pin EPS can deliver at the stock speed anyhow. Now, if we make a jump to 10/20 processors at some point and the TDP is significantly higher than the current 95w TDP of the 9900k, then it may become a necessity rather than an option.

Even so, we had much higher TDP units drawing more power on previously gens and the single 8 pin EPS was plenty. Look at the 7820x. That's an 8 core 16 thread CPU with a 140w TDP, and even then the extra four pin on the Skylake and Kaby lake X boards was optional and only recommended when extreme overclocking was part of the configuration so unless something changes, or has changed, in the fundamental architecture of the power delivery system, I don't see it becoming a necessity anytime soon.

I could be wrong, wouldn't be the first time for sure, but I think that's on point.

That's the issue, it says you can, but then who knows what they really mean by it?

I foresee MORE issues as time goes on with this.

Yeah it would be an exercise in stupidity not to connect both if running a 9900K.

I am running a Z370 MB and a 9900K @ 5 GHZ MCE that has a single 8 Pin, but it's not a low-end MB, it's an AORUS Z370 Gaming 5 that has very good VRMS, etc. The Gaming 5 is one of best OCing MB on the market and some say even better than the Gaming 7 power wise.

Not sure what they are doing with the Z390 MB's and how the extra power connection really works, I am sure however that it would be different between manufactures.


I wonder if that's any part of what made the FX-9590 suck so hard.
I'm not sure I've seen a PSU with 2x CPU power cables, although the biggest unit I've bought was only 650W.

Rogue Leader


Seasonic Prime Titanium 650w has it. But thats kind of a special case.

Seasonic Prime Series 750W (all).

Seasonic Prime Titanium 650W and up.

EVGA G2 750W

Most High Quality 750W and above Modular PSU's have them.

However not the garage units a lot of people tend to recommend.


Personally I think a lot of people need to start rethinking their recommendations of PSU's and what they are recommending.

Still seeing a lot of severe under recommending...

However I am aware of the politics involved in some of the brands and units.... Wrong as it really is.

We might start see a lot of blown systems here soon... :ange:

With the review of the Great Wall PSU on GN that was in the Wal-Mart system...

Was reading the comments and I can't believe how delusional people really are so I expect things to get much worse as people starting buying more generic PSU's.

I couldn't believe what I was reading, that's how ignorant it was.

What Steve said was taken out of context bigtime...… So yeah I expect things to get much worse.

Rogue Leader


Its already bad and been bad forever. On here all the time people drop $700 on a GPU no problem but you tell them to spend $90 on a PSU and they are all like "ZOMG I CAN'T AFFORD THAT!"

Expect it to get a lot worse than it is now.

But yeah it has been bad already.


Not always. Often they KNOW they should, but choose not to, because they are CHEAP. Stupid just happens to be what they become after making the choice to BE cheap. But in some cases I concur that a lack of intellect is probably a contributing factor BEFORE the decision to be cheap.

Rogue Leader


But my friend ran a Quad SLI 980ti setup on an Apevia, so clearly it must "work fine"


Not only does it work fine, but it is an exemplary model of what I power supply should be, so I recommend you get FOUR and run them all simultaneously. Which is probably still not going to be enough BUT at least you won't have to cave in to recommendations and go with a DIFFERENT model that way.

But I saw this YT Video of a guy running an SLI GTX 1080Ti setup on a generic 450W PSU that came with his case. So clearly everyone must be mistaken....

Being CHEAP... Trying to get over, something for nothing is stupid in the 1st place.

And then they make the completely braindead choice of actually buying, even more idiotic.

CPU - $400
Cooler - $20
MB - $200
RAM - $80
GPU - $800
HD - $20
Case - $30
KB - $150
Mouse - $150
PSU - $20
Monitor - $500

Looks very much like builds we see a lot.

The MB and the PSU are the 2 most important parts of the system.

And those are the 2 things MOST people will cheap out on 1st.... It's absolutely idiotic.


If not going to overclock, spending big on the motherboard isn't really necessary. I agree if you get a K series CPU, you should buy a Z series board. But a B360 is fine for any locked CPU, and B450 is fine for Ryzen users not looking to push their clocks. No 2 ram slot boards, unless it is an ITX board, though.