MEG Z390 when is 2nd EPS cable REALLY needed?

[docdj]

I am planning to buying an MSI MEG Z90 mobo. PcPartPicker says it "requires" a PSU with TWO 8-pin EPS connections. MSI says you only need ONE, unless you are overclocking. I DO plan to OC an I7-8700K a little (20-30%), but I don't know if that means I REALLY need a PSU with dual 8-pin EPS connectors (Corsair RM850i/EVGA G3 850) vs their step-down 650W models. I am planning to use a Noctua NH-D15S cooler because need a long-term (years) stability w/o worrying about leaks, refilling coolant, etc. So It's obvious(?) that I won't be OC'ing  much. GPU: single RX 580 4GB.

 

I know the cost diff is small (compared to the rest of my choices), but advice from others would make me feel a LOT better about my choice. (I also don't want to raise my electricity bill a lot).

[TrigrH]

9 minutes ago, docdj said:

I am planning to buying an MSI MEG Z90 mobo. PcPartPicker says it "requires" a PSU with TWO 8-pin EPS connections. MSI says you only need ONE, unless you are overclocking. I DO plan to OC an I7-8700K a little (20-30%), but I don't know if that means I REALLY need a PSU with dual 8-pin EPS connectors (Corsair RM850i/EVGA G3 850) vs their step-down 650W models. I am planning to use a Noctua NH-D15S cooler because need a long-term (years) stability w/o worrying about leaks, refilling coolant, etc. So It's obvious(?) that I won't be OC'ing  much. GPU: single RX 580 4GB.

 

I know the cost diff is small (compared to the rest of my choices), but advice from others would make me feel a LOT better about my choice. (I also don't want to raise my electricity bill a lot).

under liquid nitrogen.

[Jurrunio]

Depending on the actual board (there are a few MEG Z390), you either try blow the board up or going liquid nitrogen on an 9900k, that you'll need the second EPS connector plugged in

[Spotty]

You won't have any issues overclocking an i7 8700k on that motherboard with a single 8pin EPS connector. Not unless you're going for super high overclocks using sub-ambient cooling with a chiller or LN2 or whatnot. No need for dual 8pins with regular overclocking.

If for whatever reason you really want an additional EPS connector for the motherboard, the RM650i has 3 sockets for 6+2pin/8pin CPU on the PSU side. You could purchase an additional EPS12v cable for $4 from Amazon/Corsair website if you really wanted it. Just search for "Corsair Type4 8-pin EPS12v CPU cable"

https://www.corsair.com/us/en/Categories/Products/Accessories-|-Parts/PC-Components/Power-Supplies/Type-4-Sleeved-black-8-pin-(4%2B4)-ATX12V-EPS12V-Cable%2C-compatible-with-all-CORSAIR-type-4-pin-out-PSU/p/CP-8920141

Probably able to find replacement cables for the EVGA G3 on their website as well, but the RMi is the better unit between the two.

 

5 minutes ago, docdj said:

(I also don't want to raise my electricity bill a lot).

Power supplies only draw from the wall what the system demands. An 850w PSU doesn't consume 850w (or a little more like 950w due to efficiency loss) unless the system actually requires 850w. Doesn't change based on the wattage of the PSU. That's just a maximum rating for what the unit can do if needed.
Whether you're using an 850w PSU or 650w PSU, with an 8700k + RX 580 4GB you'll probably be consuming under 300w while gaming.

[Guest]

Why that board if you are only running an 8700K ? You could easily go with something like a Gigabyte Z390 Aorus Elite/Pro for much less. Even the entry level Z390 UD wouldn't break a sweat with that cpu.

[docdj]

Thanks for everyone's VERY helpful comments.

I'm looking at the MEG Z390 ACE because the Aorus Elite has only 2 PCIE full-size slots and Aorus Ultra and Pro appear to have have DPC latency problems, causing "clicks" in audio and lag in mouse response: https://www.hardocp.com/article/2017/11/27/gigabyte_z370_aorus_ultra_gaming_motherboard_review/4

I am also l looking at the ASUS Maximus XI Hero wifi, because it has onboard HDMI port (for backup).

 

And thanks to your post, I'm now looking at the i7-9700K which is not as much more than the 8700k than it used to be.

 

Does that make a diff?

[Guest]

7 hours ago, docdj said:

Thanks for everyone's VERY helpful comments.

I'm looking at the MEG Z390 ACE because the Aorus Elite has only 2 PCIE full-size slots and Aorus Ultra and Pro appear to have have DPC latency problems, causing "clicks" in audio and lag in mouse response: https://www.hardocp.com/article/2017/11/27/gigabyte_z370_aorus_ultra_gaming_motherboard_review/4

I am also l looking at the ASUS Maximus XI Hero wifi, because it has onboard HDMI port (for backup).

 

And thanks to your post, I'm now looking at the i7-9700K which is not as much more than the 8700k than it used to be.

 

Does that make a diff?

That review is for the Z370 Aorus Ultra Gaming though, not the Z390 Aorus boards. Also it says that the DPC latency is solid, unless I misread it ?

 

If you are looking at the Asus Maximus Hero XI then the Aorus Master is in that price range. That has a HDMI port at the rear as well. The Gigabyte Z390 Designare is also around the same price. That also has Dual Lan and Thunderbolt 3 at the rear i/o as well as a HDMI port.  

 

The Asus board is 'OK' but the VRM is somewhat lacking compared to any of the Gigabyte Aorus boards. The only real plus is that Asus has a much better/smoother bios.

 

The 9700K will run fine on any Z390 board. The 9900K is the one you need to be more careful with regarding board selection.

[Guest]

1 hour ago, Queen Chrysallis said:

@Jurrunio @Spotty

 

Tho there's no harm on having it plugged in even when not planning high OCs, right?

I'm under the impression that having it plugged in would provide some sort of "headroom"

So it would never get even close to putting too much pressure when powering with only 1 EPS

You won't get close to maxing out the 8 pin under normal usage/overclocking. You can plug both in if you have the connectors on your psu but you don't need to. It might be different for a higher end cpu i.e a 32 core TR4.

[Guest]

20 minutes ago, Queen Chrysallis said:

I had a 9900K in mind when i asked it as it is a power hungry chip

Still fine with a single 8 pin.

[Jurrunio]

2 hours ago, Queen Chrysallis said:

@Jurrunio @Spotty

 

Tho there's no harm on having it plugged in even when not planning high OCs, right?

I'm under the impression that having it plugged in would provide some sort of "headroom"

So it would never get even close to putting too much pressure when powering with only 1 EPS

there's no harm, just no benefits either (tho not having empty headers can satisfy OCDs)

 

9 hours ago, docdj said:

And thanks to your post, I'm now looking at the i7-9700K which is not as much more than the 8700k than it used to be.

 

Does that make a diff?

Z370 doesnt necessarily come with 9th gen support, but Z390 all do. Similar performance and power draw to an 8700k, but easier to cool.

 

9 hours ago, docdj said:

Thanks for everyone's VERY helpful comments.

I'm looking at the MEG Z390 ACE ... Aorus Elite ... ASUS Maximus XI Hero wifi,

Gigabyte especially expensive? Because in US prices, it's Ace versus Master versus M11 Hero. Yes, Master is different to the Elite, Pro, Ultra and Designaire.