System Compatibility and Stability

[onkardevil]

Greetings,

I wanted to discuss a couple of things with you experts in this post and would like to have your opinions.

1. PSU and GPU Compatibility:
I own a Corsair RM850e (2023 version, comes with a 12vhpwr cable) fully modular PSU which I have paired with my MSI RTX 3090 Suprim X. I have it plugged in and the system seems to work, I just wanted to understand something from the safety and stability point of view. The RM850e comes with only 4x points for CPU/PCIe (2 each) with 2x EPS cables (both of which are taken by my Z790-H Motherboard) and 1x 6+2 PCIe and 1x 6+2 with a pig-tail 6+2 connector, the 3090 however has 3x PCIe connector points. I have noticed some markers going online mentioning that it is best to not use a pig-tail connector on high power draw cards, and the 3090 is rated at 420w consumption. My question is, is the setup of this GPU with 2x dedicated and 1x pig-tail connections to the PSU safe enough to not catch fire? (I don't care much about getting every drop of performance out of it). If it is unsafe, what should be my steps forwards? Can I make this system work as it is? or do I need to undervolt the GPU?

2. DDR5 RAM Compatibility:
I built the system up and did a Bench Test, which went well, however, during the BIOS update from v1202 to v1501 for the Asus ROG Strix Z790-H Gaming WiFi motherboard, the system did not post with the DRAM orange light solid. I flashed the other versions of the BIOS into the board, which sometimes worked, but not for long. I started troubleshooting and the system posted with 1 RAM stick removed from the 2. This lead me to a Reddit trail where the user mentioned that the RGB on the RAM stick was so much that it did not boot without the XMP enabled.
So, upon trial of: removing one RAM stick > booting the PC > updating the BIOS > enabling the XMP > installing the other RAM stick, the system started working completely fine.
The RAM here is G.Skill Trident Z5 RGB 32, 16x2, DDR5 6000.

SPECS: Intel i7 14700k | Noctua NH-D15s | Asus Strix Z790-H Gaming WiFi | G.Skill Trident Z5 RGB 32 | MSI RTX 3090 Suprim X 24G | Adata XPG Gammix S70 Blade 1+2TB | Corsair RM850e 2023 | Corsair iCUE 4000X

Hope to have your expert views and recommendations on the above topics! Thank you.

[OddOod]

Take note, we aren't actually experts, just knowledgable

32 minutes ago, onkardevil said:

1. PSU and GPU Compatibility:

Is it unsafe? No. Could it be unstable? Maybe. Should you replace one of the CPU 8pins with a PCI 8pin? It depends on your CPU. A single 8pin will deliver almost 400W to the CPU, your 14700k turbos up to 250W which means it only *needs* one. Given that your GPU can suck back almost twice as much power, I'd personally build it with 1 to the CPU and 3 to the GPU, but if you currently have a build you're happy with and is stable, I'd let sleeping dogs lie

 

37 minutes ago, onkardevil said:

2. DDR5 RAM Compatibility:

Yeah, DDR5 is still very new and there are kinks being worked out. This honestly isn't surprising. It's one of the reasons I tend to push non-RGB DIMMS

[Alex Atkin UK]

58 minutes ago, onkardevil said:

I have noticed some markers going online mentioning that it is best to not use a pig-tail connector on high power draw cards, and the 3090 is rated at 420w consumption.

This is simply people being paranoid, as you will note the 12VHWPR that comes with the PSU only uses TWO connections on the PSU - so its basically the same as using two PCIe pigtails (which I did on my 4090 before the new cables came out).

 

Its mostly relevant if you have a cheap PSU that might not have rated their cables safely, completely irrelevant when using a Tier A PSU.

[onkardevil]

Thank you for your inputs!
I will keep the setup as it is and run a few tests to see if it causes any issues.