Is it worth going for RMx/RMi series over RM?

danlightbulb · 2 Sep 2020 at 01:08

Gonna need a new PSU for new GPU as Im only on 550W.

Im thinking 850 W will give me more than enough headroom and the prices are not much different between 750W and 850W.

But is it worth going for RMx series over RM for Corsair (my favoured brand currently). Any other brands I should be considering?

mickyflinn · 2 Sep 2020 at 13:50

Super flower leadtek 111 are excellent psu but only has a 7 year warranty.

The Rmx uses high quality ( japaniese )capacitors.

pewpew · 2 Sep 2020 at 16:39

What GPU are you thinking of? If you are looking at the new NVIDIA/AMD offerings this year id hold out until reviews/3rd party cards are released before purchasing, its possible that 3rd party cards have different power requirements.

I just got a RM 650x and would highly recommend this series good build quality, beware the capacitors are huge on the cables and make cable management tricky.

IMO the modest price increase for better fan, better capacitors and better performance is worth it.

danlightbulb · 2 Sep 2020 at 16:50

pewpew said:
I just got a RM 650x and would highly recommend this series good build quality, beware the capacitors are huge on the cables and make cable management tricky.

Which end of the cables has the capacitors? Cant make them out at all on the stock photos on this site.

pewpew · 2 Sep 2020 at 17:19

danlightbulb said:
Which end of the cables has the capacitors? Cant make them out at all on the stock photos on this site.

It's at the motherboard end they reduce ripple, it's nothing to worry about providing you have a modern case just be aware of it i was shocked when replacing my older PSU, I ended up using some sleeved extensions.

https://youtu.be/tUdou_OfVWA?t=156

https://www.overclock3d.net/reviews/power_supply/corsair_rmx_psu_review/1

mattyfez · 4 Sep 2020 at 09:42

I just went for an RM as it still has 10 year warranty.

danlightbulb · 4 Sep 2020 at 14:19

Question about the cables you get with modular power supplies:

From looking at the Corsair manual, each PCIe cable has two connectors at the end. But with GPU's is it better to run a separate cable for each power connector? That means you'd then have 2 dangling cables at the GPU with nowhere to go?

What do you do about this? Nothing, or try and get single connector cables from elsewhere?

mattyfez · 4 Sep 2020 at 14:42

Id always use 2 discrete cables if at all possible, see other threads about melting plugs.

Can be unsightly though with certain cables, careful use of zip ties can minimize it.

Edit, my RX480 just has one 8 pin connector though, so I'm just using one cable. Which still has some dangley bits, but I don't have a side window, so I don't care

merlin6r · 7 Sep 2020 at 22:01

danlightbulb said:
Question about the cables you get with modular power supplies:

From looking at the Corsair manual, each PCIe cable has two connectors at the end. But with GPU's is it better to run a separate cable for each power connector? That means you'd then have 2 dangling cables at the GPU with nowhere to go?

What do you do about this? Nothing, or try and get single connector cables from elsewhere?

This really is the age old question.

In reality it doesn't really make a difference unless you are at the very upper limit of what that PSU can supply on that cable.

The only valid evidence I've ever seen was something like a 2080Ti overclocked that managed like 10mhz higher using two separate cables.

Try both ways, I bet you'll see no difference...

mattyfez · 8 Sep 2020 at 18:45

merlin6r said:
This really is the age old question.

In reality it doesn't really make a difference unless you are at the very upper limit of what that PSU can supply on that cable.

The only valid evidence I've ever seen was something like a 2080Ti overclocked that managed like 10mhz higher using two separate cables.

Try both ways, I bet you'll see no difference...

It's not about improving performance, it's about balancing the load over more than one cable so they wont get as warm/hot as a single cable.

merlin6r · 8 Sep 2020 at 21:09

It doesn't make any difference. If the PSU is spec'd to support two graphics cards it can handle one graphics card on one cable.

pp111 · 16 Sep 2020 at 08:42

The thing with getting a power supply too big is that it wanders out of it's optimal performance range, meaning you won't achieve that gold performance. Not that it makes a huge difference, just sayin'!

The more you spend the better quality you get, but I find that a PSU is more likely to get thrown out because of a noisy fan and or age related whine, so I am not sure about the real world difference between good and very good.

OZONE · 17 Sep 2020 at 08:56

merlin6r said:
It doesn't make any difference. If the PSU is spec'd to support two graphics cards it can handle one graphics card on one cable.

Seasonic themselves recommend using separate PCIE cables for powering up your GPU

merlin6r · 17 Sep 2020 at 22:47

OZONE said:
Seasonic themselves recommend using separate PCIE cables for powering up your GPU

This question goes round and round. If you google you'll find it on dozens of forums. I've never seen anyone have a problem from using 1 cable.
I've tried it both ways and bench marked. No difference in heat or performance, and a single cable wasn't any hotter than 2 separate cables.

If 1 cable couldn't safely supply 2 plugs then all manufacturers would be supplying single pci-e plug cables.

Some people will always swear by using 2 separate cables, some will only ever use one. I've tried both several times.
This question will continue to be asked because there isn't a 'wrong' way to do it.

I stand by my original stance that it just doesn't matter.

mattyfez · 18 Sep 2020 at 01:09

merlin6r said:
I stand by my original stance that it just doesn't matter.

And I shall stand by what a reputable PSU manufacturer recommends, that it does matter. Seasonic have nothing to gain by making that recommendation, they could ship their units with fewer cables if that were the case and save some cost.

merlin6r · 18 Sep 2020 at 02:00

mattyfez said:
Seasonic have nothing to gain by making that recommendation, they could ship their units with fewer cables if that were the case and save some cost.

Well they kinda do ship it with fewer cables. A PSU that supports 2x graphics cards comes with 2 cables. That's 1 cable for each card.
If it truly needed 2 cables per card they would have to include 4 cables. With 1 plug on each instead of 2 plugs on each.

Hopefully when they send out the new 12 pin plugs it will split into 2 plugs to go into the PSU and it'll be decided once and for all...