Question Tips on choosing a PSU ?

[richdmccarty]

I'm looking for a power supply for a new mid-tier gaming build but I don't know of many factors to choose between different PSUs.
I've only considered the wattage of my build, to make sure the PSU is at least gold rated, and that the manufacturer is reputable. Any other factors I should consider?
Regarding wattage, I'm planning on getting the ASUS PRIME GeForce RTX 5070 and the documentation recommends at least 750W and PC part picker says my build needs an estimated 436W.

I did some shopping and I'm thinking of going with either 1) CORSAIR RM750e (2025) or 2) MSI MAG A750GL but I'm having trouble choosing between the two because the specs have different verbiage.

For example, CORSAIR RM750e (2025) says it has 3 PCIe connectors but MSI MAG A750GL says it has 1 (450W) PCI-E 5.0 (16 pin) and 3 PCI-E (6+2 pin). Should I do further research on the corsair PSU to see the specific type of PCIe connectors?
I'm also planning on getting motherboard Gigabyte B650E Aorus Master. The specs of the board says it uses 1 x 24 ATX pin and 2 x 8 ATX 12 V pin but I don't see that mentioned on the specs for either PSU. The RTX 5070 uses 1 x 16-pin which is mentioned on the MIS PSU as 1 (450W) PCI-E 5.0. No mention of 1 x 16-pin on the corsair.

 

[Aeacus]

but I don't know of many factors to choose between different PSUs.

Since PSU powers everything, it is the most important component inside the PC.
Hence why NEVER cheap out on PSU! Also, never buy used PSU either.

As for where to start learn about PSUs, this guide here is good start (a bit long read though),
link: https://forums.tomshardware.com/thr...pply-discussion-thread-toms-hardware.3212332/

Any other factors I should consider?

Yes, reputable review.

Further reading: https://hwbusters.com/best_picks/best-atxv3-pcie5-ready-psus-picks-hardware-busters/

All those PSUs are reviewed by reputable reviewer (Aris) and he has made chart to show the best PSUs. Picking any of those means good/great build quality PSU.


Another is warranty.

PSU reliability can be seen from the warranty length it has been given.
In a nutshell:
up to 2 years - terrible reliability
3 years - poor reliability (e.g Corsair VS/CS)
5 years - mediocre reliability (e.g Be Quiet! Straight Power 11, Seasonic G12, Corsair CX/CXF)
7 years - good reliability (e.g Seasonic Core/Focus GM, Corsair TX/AX)
10 years - great reliability (e.g Seasonic Focus GX/PX, Corsair RMx/HX/HXi/AXi)
12 years - superb reliability (e.g Seasonic Vertex/PRIME)

So, aim for a 10 year warranty PSU. 7 year warranty would be bare minimum.

CORSAIR RM750e (2025)

Mediocre quality PSU. Enough for office PC without dedicated GPU. But not for any with dedicated GPU (e.g gaming rig).

If you want Corsair, look for: RMi/RMx/HXi/AXi.

MSI MAG A750GL

Fun fact: no warranty.

Official specs: https://www.msi.com/Power-Supply/MAG-A750GL-PCIE5

It doesn't say anywhere on official specs page about PSU's warranty length.

MSI is known for PSU warranty shenanigans.

For comparison, here's my PSU specs page (i have 650W unit),
link: https://seasonic.com/prime-titanium/

Warranty is listed as one of the initial specs.
Also, my PSU has several reputable reviews (including review by Aris).

No mention of 1 x 16-pin on the corsair.

Any PSU that is ATX 3.0 or ATX 3.1 has that 16-pin PCI-E power connector. Corsair unit doesn't have it since it is older, ATX 2.5 PSU.

There are adapters out there, that transform 8-pin PCI-E to 16-pin PCI-E.

 

[dwd999]

I consider the number of 8-pin connectors to be a primary factor. Combine that with the number/type of connectors on your chosen graphics card. If you choose a graphics card with 3 8-pin connectors and you need 2 for your motherboard then your psu should have at least 5 8-pin connectors. There are even motherboards now which prefer 3 8-pin connectors. So I would say get as many 8-pin connectors as you can find.

 

[Aeacus]

If you choose a graphics card with 3 8-pin connectors and you need 2 for your motherboard then your psu should have at least 5 8-pin connectors.

Looks like you do not know the difference between 4/8-pin 12V EPS and 6/8-pin PCI-E.

One is solely for CPU power, while other is for GPU/MoBo/peripheral power. Also, the two connectors, despite having same amount of pins, have different pinout and are keyed differently.

 

[geofelt]

Good comments from Aeacus above.
Particularly about how to estimate quality from the warranty.
Yes, you will pay more for a 10 year warranty psu.

I would not consider efficiency(gold/silver/platinum... etc) as a factor.

I would look to buying a stronger psu than what is currently recommended.
From 750w to 850w or more.

1. Modern graphics cards can have very high temporary power spikes that a stronger psu can handle.
2. A stronger psu can support a stronger future graphics card upgrade. That is the most common upgrade done.
3. A stronger psu will be quieter and more efficient running in the middle third of it's range.
4. The incremental cost of going from, say, 750w to 850w is usually small.
5. A extra strong psu will only use the power demanded of it, regardless of the max capability.

 

[--SID--]

Some folks don't know what they're talking about. Corsair RM 750 e (2025) is the ATX3.1 version of the RMe line up. This PSU is totally fine and comes with a 12v 2x6 connector and a 7 year warranty. It's a silent unit too. A lot more silent than than the MSI MAG A-GL

 

[Eximo]

Yeah, the RM750e / RM850e are decent when they are priced well, sub $100. They don't fair too well when you start looking at the $120+ mark.

I've taken up reading through Cybenetics reviews for silence and efficiency. I then cross reference it with the slightly dated PSU tier list, and the one managed by PCMR.

https://www.cybenetics.com/index.php?option=power-supplies

lambda for noise, ATX for efficiency.

PSU Tier List rev. 17.0g - Cultists Network

PSU Tier List will help you to choose the best PSU out of hundreds of models on the market. From budget to the highest end Power Supplies.

cultists.network

Direct google dock link:

https://docs.google.com/spreadsheet...RB6Xt6JWkc/edit?gid=1719706335#gid=1719706335

Reminds me of the old Who's Who in Power Supplies that Tom's had back in the day. Very useful when you can spot the OEM behind the PSU label and compare similar models under, perhaps, unfamiliar names.

 

[Aeacus]

Some folks don't know what they're talking about. Corsair RM 750 e (2025) is the ATX3.1 version of the RMe line up. This PSU is totally fine and comes with a 12v 2x6 connector

I didn't cross-validate the info from official specs. Instead, i went with what OP said about the PSU's connectors.

Then again, could be, that OP doesn't know that 12V-2x6 connector is the very same 16-pin as they are looking for. Hence why thinking RMe 2025 doesn't have said connector.
RMe 2025 secs: https://www.corsair.com/us/en/p/psu...ular-low-noise-atx-power-supply-cp-9020295-na

 

[dark_globe]

i would not recommend even a 3.1 refit of RMe for an enthusiast build .
simply because 850w model costs exactly the same as RMx which is a superior model with
better internal parts and better warranty .
if 850w RMe 2025 was priced at $85 (street price) than maybe it would be a
somewhat valid option for more budget oriented systems ...

 

[richdmccarty]

Since PSU powers everything, it is the most important component inside the PC.
Hence why NEVER cheap out on PSU! Also, never buy used PSU either.

As for where to start learn about PSUs, this guide here is good start (a bit long read though),
link: https://forums.tomshardware.com/thr...pply-discussion-thread-toms-hardware.3212332/


Yes, reputable review.

Further reading: https://hwbusters.com/best_picks/best-atxv3-pcie5-ready-psus-picks-hardware-busters/

All those PSUs are reviewed by reputable reviewer (Aris) and he has made chart to show the best PSUs. Picking any of those means good/great build quality PSU.


Another is warranty.

PSU reliability can be seen from the warranty length it has been given.
In a nutshell:
up to 2 years - terrible reliability
3 years - poor reliability (e.g Corsair VS/CS)
5 years - mediocre reliability (e.g Be Quiet! Straight Power 11, Seasonic G12, Corsair CX/CXF)
7 years - good reliability (e.g Seasonic Core/Focus GM, Corsair TX/AX)
10 years - great reliability (e.g Seasonic Focus GX/PX, Corsair RMx/HX/HXi/AXi)
12 years - superb reliability (e.g Seasonic Vertex/PRIME)

So, aim for a 10 year warranty PSU. 7 year warranty would be bare minimum.


Mediocre quality PSU. Enough for office PC without dedicated GPU. But not for any with dedicated GPU (e.g gaming rig).

If you want Corsair, look for: RMi/RMx/HXi/AXi.


Fun fact: no warranty.

Official specs: https://www.msi.com/Power-Supply/MAG-A750GL-PCIE5

It doesn't say anywhere on official specs page about PSU's warranty length.

MSI is known for PSU warranty shenanigans.

For comparison, here's my PSU specs page (i have 650W unit),
link: https://seasonic.com/prime-titanium/

Warranty is listed as one of the initial specs.
Also, my PSU has several reputable reviews (including review by Aris).


Any PSU that is ATX 3.0 or ATX 3.1 has that 16-pin PCI-E power connector. Corsair unit doesn't have it since it is older, ATX 2.5 PSU.

There are adapters out there, that transform 8-pin PCI-E to 16-pin PCI-E.

This was immensely helpful. I found the power supply difficult to shop for and this was informative. Based on other responses I've got I'm going with Corsair RMx 750W.

 

[richdmccarty]

I didn't cross-validate the info from official specs. Instead, i went with what OP said about the PSU's connectors.

Then again, could be, that OP doesn't know that 12V-2x6 connector is the very same 16-pin as they are looking for. Hence why thinking RMe 2025 doesn't have said connector.
RMe 2025 secs: https://www.corsair.com/us/en/p/psu...ular-low-noise-atx-power-supply-cp-9020295-na

Yeah I found the 16-pin connector had different names during my research and was a little confused. I saw it references as 12V-2x6, 12VHPWR, and PCI-E 5.0 (16 pin). Now I know that all ATX 3.1 compliant PSUs should have that connector which is one less thing for me to worry about.

 

[Aeacus]

I'm going with Corsair RMx 750W.

Solid PSU. Will last you for a long time. 👍
Also, best price-to-performance ratio Corsair PSU you can get.

I saw it references as 12V-2x6, 12VHPWR, and PCI-E 5.0 (16 pin).

There are slight differences to those names;

PCI-E 5.0 isn't a PSU connector. Instead, it is PCI-E revision that latest MoBos have. Used by latest GPUs (e.g RTX 50-series) and M.2 drives (e.g Samsung 9100 Pro).

16-pin PCI-E is unofficial naming of the power connector. Some may call it 12+4 pin as well, since the connector actually has 12 power/ground pins while the remaining 4 are sense pins.
It's continuation of the official naming of: 6-pin PCI-E, 8-pin PCI-E, 12-pin PCI-E (latter used only on RTX 30-series and forerunner of the 16-pin PCI-E).

12VHPWR is official name of the connector itself and strictly for ATX 3.0 PSUs. The 1st iteration of the connector.
12V-2x6 is official name of the connector itself and strictly for ATX 3.1 PSUs. 2nd iteration of the connector.
Differences written here: https://www.corsair.com/us/en/explo...units/evolving-standards-12vhpwr-and-12v-2x6/