[SOLVED] How much clearance does a gpu fan need?

[Bongert]

As the question says. i was wondering about the size of the 3000 series cards and pondered a bunch of questions, for example why motherboard manufacturers still bother putting PCIe x1 slots between the two PCIe x16 slots or how close a second card could go against the fans of a gpu before it starts to affect the cooling performance of said gpu.
I recently heard about deshrouding and was interested in trying it once i knew if the morpheus II or 8057 or an eventual third model would be compatible with the 3000 series. the main problem i heard about deshrouding is the ridiculous size that a card would get. depending on the fans used one would go well beyond triple slot size.
I was also wondering why mainboard manufacturers would put the first, metal reinforced PCIe x16 slot at the very top instead of the bottom no following slots beneath it. just put an M.2 slot there and any addidional cards could go above the GPU without affecting cooling performance.
but back to the main question of how much clearance a fan needs. in my current setup i have two GPUs with two PCIe x1 slots between them, one covered by the top gpu and the second visible and i would consider that enough clearance. but the 3000 cards would barely fit and i wonder how that affects cooling

 

[Darkbreeze]

The bus has better performance the closer it is to the CPU. The longer the bus trace is, the more likely it is for it to have problems with signal reflection and degradation. That goes for most buses really. Then there is the additional fact that putting the graphics card CLOSER to the top of the power supply is probably going to raise the GPU temperature by a few degrees in most cases, whereas keeping it further away makes for a better allowance that the incoming ambient air will mix with any heat coming off the top of the PSU and mitigate it's contribution to an elevated GPU temperature. It also move the GPU closer to the exhaust ports at the top and rear of the case which might lend some additional expediency to getting heat shedded from the GPU out of the case faster.

As far as using TWO cards, that's an unrealistic question for this generation of graphics card. Given the performance of these cards, there is NO reason at all why anybody would need to run two cards. A single card can support any choice of resolution or performance desired aside from stupidly out of reach configurations like 8k or multiple 4k panels. Additionally, Nvidia has already said they are officially not supporting SLI on anything from this architecture except for the 3090 and if one comes later, perhaps the 3090 ti.

SLI is dead anyhow and mostly nobody is including SLI profiles for any of the latest games anymore anyhow. So unless you're planning to run dual 3090's for some kind of over the top configuration like 4k surround or 8k ultra, there isn't even any reason to be worried about that and if you ARE going to do that, then you can certainly afford a case and E-ATX motherboard that will put the cards far enough apart that it wouldn't be a concern in the first place.

 

[Bongert]

The bus has better performance the closer it is to the CPU. The longer the bus trace is, the more likely it is for it to have problems with signal reflection and degradation. That goes for most buses really. Then there is the additional fact that putting the graphics card CLOSER to the top of the power supply is probably going to raise the GPU temperature by a few degrees in most cases, whereas keeping it further away makes for a better allowance that the incoming ambient air will mix with any heat coming off the top of the PSU and mitigate it's contribution to an elevated GPU temperature. It also move the GPU closer to the exhaust ports at the top and rear of the case which might lend some additional expediency to getting heat shedded from the GPU out of the case faster.

As far as using TWO cards, that's an unrealistic question for this generation of graphics card. Given the performance of these cards, there is NO reason at all why anybody would need to run two cards. A single card can support any choice of resolution or performance desired aside from stupidly out of reach configurations like 8k or multiple 4k panels. Additionally, Nvidia has already said they are officially not supporting SLI on anything from this architecture except for the 3090 and if one comes later, perhaps the 3090 ti.

SLI is dead anyhow and mostly nobody is including SLI profiles for any of the latest games anymore anyhow. So unless you're planning to run dual 3090's for some kind of over the top configuration like 4k surround or 8k ultra, there isn't even any reason to be worried about that and if you ARE going to do that, then you can certainly afford a case and E-ATX motherboard that will put the cards far enough apart that it wouldn't be a concern in the first place.

Second GPUs becoming redundant i agree, but there is still market for WiFi Cards, raid Controllers or PCIe SSDs that would sit directly under the GPU. I dont know how much heat a PSU actually generates but i imagine with enough headroom in wattage there wouldnt be that much heat generated that the fan couldnt take care of.

 

[Darkbreeze]

I wouldn't use the first slot directly below your graphics card's lowest point. So if the fans are sitting slightly above the slot that is two slots down from the actual slot the graphics card is seated into, then I wouldn't use that slot, but using the slot three slots down should be fine. Basically, there should probably be at least one empty slot in between the fans and the next add in card, for most boards. In some cases, that might not be an option so then it becomes a case of "it is what it is" unless you are willing to buy another board.

The fact is that these days MOST motherboards come with 99% of what 99% of buyers NEED to have, integrated into the motherboard. So for most people, it isn't a problem. For those that it IS a problem for, that want a GINORMOUS graphics card and additional expansion cards as well, it's probably not unrealistic to say that in that case, get a bigger case and an E-ATX board with a configuration that can accommodate it. Otherwise, it is what it is.

Most gamers using a huge graphics card probably aren't particularly worried about additional add in card functionality. Boards have wifi. Get one WITH it if you NEED it. Otherwise, use LAN, which is faster and more reliable anyhow. Boards, pretty much all of them these days, have onboard RAID controllers. In this modern era of cheap SSDs and NAS boxes, RAID is largely a waste of time and a poor choice for most people anyhow. Plus, SSD RAID offers little or in some case WORSE performance than a straight NVME PCIe drive would give you anyhow.

PCIe SSD cards are largely dead these days. There is really little need to go this route when most boards have one, two or three NVME M.2 drive slots anyhow.

 

[Bongert]

I wouldn't use the first slot directly below your graphics card's lowest point. So if the fans are sitting slightly above the slot that is two slots down from the actual slot the graphics card is seated into, then I wouldn't use that slot, but using the slot three slots down should be fine. Basically, there should probably be at least one empty slot in between the fans and the next add in card, for most boards. In some cases, that might not be an option so then it becomes a case of "it is what it is" unless you are willing to buy another board.

The fact is that these days MOST motherboards come with 99% of what 99% of buyers NEED to have, integrated into the motherboard. So for most people, it isn't a problem. For those that it IS a problem for, that want a GINORMOUS graphics card and additional expansion cards as well, it's probably not unrealistic to say that in that case, get a bigger case and an E-ATX board with a configuration that can accommodate it. Otherwise, it is what it is.

Most gamers using a huge graphics card probably aren't particularly worried about additional add in card functionality. Boards have wifi. Get one WITH it if you NEED it. Otherwise, use LAN, which is faster and more reliable anyhow. Boards, pretty much all of them these days, have onboard RAID controllers. In this modern era of cheap SSDs and NAS boxes, RAID is largely a waste of time and a poor choice for most people anyhow. Plus, SSD RAID offers little or in some case WORSE performance than a straight NVME PCIe drive would give you anyhow.

PCIe SSD cards are largely dead these days. There is really little need to go this route when most boards have one, two or three NVME M.2 drive slots anyhow.

i just find it dumb that when buying a board with 6 pcie slots i basically only get to use two, three at the very best, jut because the layout isnt done well. and EATX shouldnt be the solution as its absolute overkill and there are only four with an AM4 socket. I paid for the whole motherboard, i wanna use the whole motherboard dammit!

 

[Darkbreeze]

People with cars that can do 150+mph want to drive fast too, but we don't always get what we want. You do have options. You have the option of using a smaller graphics card along with additional expansion cards, OR using a humongous graphics card with only one additional expansion card, in most cases. It's not a matter of the layout not being done well, because I've done overlays of multiple platform and Intel/AMD motherboards, and they are all almost identical. It's just, it IS what it IS and that's it.

As you can see below, several different brands and chipsets, all basically the same layout. It's pretty much a unified standard. The only real exceptions are whether there even ARE additional slots between the main x16 slots or not for some board models.

 

[Bongert]

People with cars that can do 150+mph want to drive fast too, but we don't always get what we want. You do have options. You have the option of using a smaller graphics card along with additional expansion cards, OR using a humongous graphics card with only one additional expansion card, in most cases. It's not a matter of the layout not being done well, because I've done overlays of multiple platform and Intel/AMD motherboards, and they are all almost identical. It's just, it IS what it IS and that's it.

As you can see below, several different brands and chipsets, all basically the same layout. It's pretty much a unified standard. The only real exceptions are whether there even ARE additional slots between the main x16 slots or not for some board models.

Ive seen some with a single PCIe x1 slot above the PCIe x16 slot which goes in the right direction but isnt what i need. sadly manufacturers dont want to innovate that much as it costs money to change the produktion process but one could always hope

 

[Darkbreeze]

True. I'd actually like to see a lot more functionality added in to the board or CPU by design, which is happening in some cases, but slowly. Unfortunately, what we have now works for most people, and niche usage isn't going to drive change very much.

 

[geofelt]

Initially, many slots were needed for add in cards such as sound cards, lan cards and storage adapters.
Over time, those functions were added into the motherboards reducing the need for slots.
But, there is also a ATX standard that defines the number and spacing of slots. 7 for ATX, 4 for MATX and one for ITX.
One pcie x 16 slot is what most need to install a graphics card.
Some new graphics cards are very wide, covering up 3 or possibly 4 slots for coolers.
Make your selections accordingly.