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Hands On with the Only Radeon RX 7900 XTX Model that has 12V-2x6 Power Connector

btarunr

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At Computex 2024, we went hands-on with the only custom-design AMD Radeon RX 7900 XTX graphics card to implement the 16-pin 12V-2x6 power connector. We've written quite a bit about this card, but weren't expecting it to be this long. This isn't just the only RX 7900 XTX with a 12V-2x6, but also the only air-cooled RX 7900 XTX that's strictly 2 slots-thick. ASRock made this card for graphics rendering farms, or AI development/inferencing builds, in which a GPU server would have 4-6 of these packed like sardines. The lateral blower helps ensure proper ventilation. The backplate is recessed to ensure better ventilation to the neighboring card.

The card sticks to AMD reference clock speeds of 2270 MHz Game clock, and 20 Gbps (GDDR6-effective) memory speed. ASRock also gave us a technical deep-dive into the card's design. For one, it's confirmed that the power connector is 12V-2x6 (H++) and not 12VHPWR. The cooling solution consists of a large copper vapor-chamber plate that makes contact with the GPU, memory, and VRM; conveying heat to an aluminium channel heatsink, which is ventilated by a high-speed lateral blower. The cooler shroud and backplate are both made of aluminium.



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That's actually a proper way to vent the heat outside of the case, through an extended vent-hole the size of that. I like it.
 
Hands on with the dumbest RX7900 XTX
 
That's actually a proper way to vent the heat outside of the case, through an extended vent-hole the size of that. I like it.
Agreed.

I dont understand why such designs and form factors were abandoned.

The current 4 slots monstrosities are a plague.
 
That's actually a proper way to vent the heat outside of the case, through an extended vent-hole the size of that. I like it.
Some of this might still be blocked by the metal between expansion slot IO plates, but it genuinely looks better than putting a useless grille of any kind there.

Curious decision to have the backplate cover only have the card, it's stated as to ensure better ventilation to the neighboring card, which is understandable, but I'd wager is unlikely.
 
At least they put the power connector in a sensible location, instead of the exact middle of the top of the card!
 
At least they put the power connector in a sensible location, instead of the exact middle of the top of the card!
Agree. Should reduce the risk of the cable damaging and becoming a fire hazard.
 
So they decided to downgrade a 7900XTX with that stupid 12V pwr connector. If its not broken, don't fix it!
 
Curious did they lower the clocks on it to make this work? Still sketchy design considering reference card power draw.
 
Agreed.

I dont understand why such designs and form factors were abandoned.

The current 4 slots monstrosities are a plague.
I don't need a jet engine, thank you.
 
The only 7900 XTX I would consider buying.
 
Reminds of the good ole HD 6000/7000 Reference model days
 
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Before everyone ragequits - This is a board specifically designed for rack-mount render farms.
 
Agreed.

I dont understand why such designs and form factors were abandoned.

The current 4 slots monstrosities are a plague.
They were abandoned in a home setting due to noise and inefficiency. They would still be available in a server setting, if water cooling hadn't become so popular for servers instead.

The reason they are inefficient is because the heat path is long. The heat generated in the first portion is transferred to the air, which then cools a later portion, which brings more heat into that air, which then cools a later portion. So on and so forth. It's a cascade of heat and inefficiency. By the end, there is a lot of heat in a small volume of air, and little capacity for that air to absorb more heat (little difference in temperature delta). To overcome this problem, a very high velocity of air is required.

Axial coolers are much more efficient because each air path is very short. They transfer heat to the air, and then the air goes away. The biggest drawback is that the heat all goes into the case, but since a case is big with big sides, you can generate a relatively high volume of air being replaced in the case without making a lot of noise.


If you think current axial coolers are monstrosities, imagine how monstrous a less efficient blower cooler would need to be in order to provide similar cooling and usability in a home setting.

 
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The only 7900xtx worth buying. 12v power cable or I'm skipping.
 
Before everyone ragequits - This is a board specifically designed for rack-mount render farms.
Exactly. I understand the whole silliness and danger of this conncetor, but at least this is exactly the situation, where the connector footprint matters, since otherwise it would impede the airflow. But on nVidia triple/quad-slot brick monstrocities, there's plenty of space to put even four PCIE 8pin connectors, easilly.
 
Agreed.

I dont understand why such designs and form factors were abandoned.

The current 4 slots monstrosities are a plague.
This cooling design is well proven and nvidia had it for years. The main reason they went from it is because gamer cards come with higher power consumption that will trigger more noise with this cooling solution. I'm happy this cooler design are for the most part gone for all gamer cards. Imagine a +500W 4090 with this. +90C, heavy throttling and screaming +60db. No thanks.
 
Hands on with the dumbest RX7900 XTX
Accurate.

Why anyone would deliberately switch from the legacy 8-pin PCIe power connectors to this ridiculous abortion 12VHPWR connector is a mystery. The only conclusion one can reasonably reach is that they are idiots. Being the 12V-2x6 (H++) variant of the same underlying trash design doesn't make it OK.
 
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Accurate.

Why anyone would deliberately switch from the legacy 8-pin PCIe power connectors to this ridiculous abortion 12VHPWR connector is a mystery. The only conclusion one can reasonably reach is that they are idiots. Being the 12V-2x6 (H++) variant of the same underlying trash design doesn't make it OK.
You're entitled to your opinion, even if it's wrong.
 
Before everyone ragequits - This is a board specifically designed for rack-mount render farms.

There is a reading and comprehension issue for some.
 
Accurate.

Why anyone would deliberately switch from the legacy 8-pin PCIe power connectors to this ridiculous abortion 12VHPWR connector is a mystery. The only conclusion one can reasonably reach is that they are idiots. Being the 12V-2x6 (H++) variant of the same underlying trash design doesn't make it OK.
When AMD now allow for the use of the new mini power connector for workstations and GPU's for rendering farms... Be you sure that they also will use same connector junk for gamer cards as well. They are all in for cutting cost on pcb design and reduce the cost of the power connector. Tragic. Greed and stupidity beat common sense.

You're entitled to your opinion, even if it's wrong.
The best connector nvidia could have used is the 8-pin EPS connectors who is rated for 300W by ATX standards. Yup, within the old ATX standard (vanilla 8-pin PCIe (6+2) is rated for 150W by ATX but can easly do +288W with modern good quality PSU). Sadly nvidia went total idiot and used this new cute mini 12+4 pin connector only to make their GPU PCB cheaper and smaller. PCI Sig and their parners should have designed this thiny modern fragile power connector 60% larger and with a real hook and latch. And nvidia should have required that all AIB partners need to use 2x 16 pin for all 4090 as Galax did for their HOF model. Stupid is the new norm nowadays. You can see all too much new modern hardware aka trash being realised nowadays and sold to dumb people. Yep, idiots everywhere.

1717766119074.png
 
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When AMD now allow for the use of the new mini power connector for workstations and GPU's for rendering farms... Be you sure that they also will use same connector junk for gamer cards as well. They are all in for cutting cost on pcb design and reduce the cost of the power connector. Tragic. Greed and stupidity beat common sense.


The best connector nvidia could have used is the 8-pin EPS connectors who is rated for 300W by ATX standards. Yup, within the old ATX standard (vanilla 8-pin PCIe (6+2) is rated for 150W by ATX but can easly do +288W with modern good quality PSU). Sadly nvidia went total idiot and used this new cute mini 12+4 pin connector only to make their GPU PCB cheaper and smaller. PCI Sig and their parners should have designed this thiny modern fragile power connector 60% larger and with a real hook and latch. And nvidia should have required that all AIB partners need to use 2x 16 pin for all 4090 as Galax did for their HOF model. Stupid is the new norm nowadays. You can see all too much new modern hardware aka trash being realised nowadays and sold to dumb people. Yep, idiots everywhere.

View attachment 350425
The purpose of the cute 12VHPWR connector and the conceptually less failure-prone variant that followed was to reduce the cost of producing the most expensive GPUs ever sold to maximize their record-setting profits. If anyone thinks this ridiculous and fragile joke connector was utilized to enhance the quality or function of the products that included it, I have some beautiful ocean beach property on the east side of Phoenix for sale that might be of interest to them.
 
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