How does the Razer Core X/Chroma actually support a 500w Card?
I know the PSU is rated 650w to power the fans, TB3 card, and 100w PD over TB, and the specs list that the max wattage of the internal GPU can be up to 500w, but the case only supplies two 6+2 8pin connectors for the GPU, which provide 150w each, plus the 75w from the PCI connection itself. Where is the other 125w coming from? or is it not able to deliver more than 375w and the 500w is untruthful? Thank you!
@bmagnien, some GPUs with two 8 pin connectors can spike higher than 300W from those connectors. It's good to have some margin.
Thanks @joevt ! It just seems like a really big 'margin' and I was wondering if Razer did something special to be able to pass that extra 125w over the 2 8 pins and the PCI slot byond the 375w that that setup is officially rated for, and how they arrived/calculated that exact 500w limit...it doesn't seem arbitrary. Also, if cards aren't designed to accept that extra power and have their own internal limits, I'm not sure what the point is or how Razer determined this was possible. I asked Razer directly and they refused to reveal how they arrived at that number or how their system operates, they said it was proprietary engineering info.
@bmagnien, power spikes can be surprisingly high. 125W margin seems fair game to me. Vega 64, for example, has been known to spike significantly for very very short periods, with a 650W PSU being recommended for it in an eGPU enclosure for this reason.
There are cards with 3x 8-pin PCIe power connectors. The Core X/Chroma's PSU is multi-rail so you could use a Y-splitter to feed such GPUs. As @mac_editor mentioned, the Vega 64 can spike in voltage draw so the 650W+ PSU was a recommendation from AMD for eGPU use. I had first hand experience using the Vega 64 LC in different eGPU enclosures and this card needs at least a 650W PSU. Tested in the Razer Core X Chroma, I could overclock the Vega 64 LC and it performed very well [build link].
@itsage, thank you! I tried to message you on reddit as I'm pairing a Core X with a 2019 16'' mbp 5600m, i9-9980hk, and am strongly considering an RTX 3090. The card will physically fit, and requires 2 dedicated 8-pins which I'll have (it comes with a 2 8-pin to 12-pin adapter for it's new 12 pin slot). My only slight concern is it recommends a 750w PSU but that's for an entire PC. Considering the Core X has a dedicated 650w PSU, I think it should be fine as the 3090 only has a 350w TGP, so even with some big spikes I feel it should cover it.
Do you have any thoughts on this, aside from the obvious cost of this endeavor and the fact that with any eGPU I'll experience bottlenecking (which I'm prepared for).
@bmagnien, Get the Mantiz Saturn Pro. It has a 750W PSU and similar aesthetic as the Ampere FE cards. The 3-slot width maybe an issue but given how beautiful these new GPUs look you may want to run them without the outer shell.
@itsage, ignore my previous post. i found your unboxing video and read thoroughly through the comments. I'll be checking the Amazon page for when the orders that arrived to Amazon warehouse will be posted live.
Is there any way for you to take measurements of your case, and give an estimate of the max height and width that you'd think this case would accommodate? And confirm if it would fit a full 3-slot width or if it's closer to 2.75 or smaller? Like you said I could always run it without the case but it'd be nice to have it fit.
Many of the 3090 AIBs are starting to be published and may be smaller or larger than the 3090 FE, but almost all of the high-end ones require 3 8-pin and suggest 750w so this would be a godsend.
Do you know if the second TB3 card takes away from the 750w overhead? Let's say I have nothing plugged in except for the MBP drawing 100w over TB3 PD, do you think it'd deliver almost all of the remaining 650w to the GPU?
Sorry for so many questions, I'm new to this and you seem to know your way around every inch of this topic. Thank you!!!