[SOLVED] B550 motheboards with single PCIe 4.0 x16 gen4 SafeSlot which is positioned slightly further from CPU

[nick1232]

Hello guys, I want to build my new PC with 30XX nVidia card which is usually 300+ mm length. I like idea of Aerocool Flo design approach with vertical video-card positioning. But they have a problem, PCI-e slot becomes positioned that way so I can't effectively use 300+ mm cards in there without case modification, what I prefer not to do.

All mobos that I have looked through use similar design patter of positioning of CPU slot and videocard slot relatively close to each other, expensive mobos with 2 PCIe 4.0 x16 gen4 slots could solve an issue, but since I have no use for another videocard slot it is waste of money.

Perhaps you encountered B550 mobos which use slightly different design and positioned PCIe 4.0 x16 gen4 slot further from CPU unit. If you have seen something like that please let me know such mobos names. I understand it is hardly possible for obvious reasons, but if some manufacturers decided to do that it would be a great help for me.

P.S. I am aware of there slim difference between in performance between between gen 3 and gen 4 but I still think it is worth a try, + PCIe 4.0 x16 gen4 slot are usually reinforced in many mobos as well + better cooling.

 

[rgd1101]

get the full side motherboard. it design that way because of the slot on the case

 

[nick1232]

get the full side motherboard. it design that way because of the slot on the case

What do you mean by full side? I considered ATX mobo but it does not matter really since position of PCI-e gen 4 is the same everythere I have looked through a dozen of different mobos of different formats, I did some size comparisons, they all copy same chipset pattern and size of how PCI-E gen 4 is positioned next to CPU. But I could miss something, what I try to check. Since mobos with a double PCIe 4.0 x16 gen4 can position second PCIe 4.0 x16 gen4 further from CPU perhaps some manufacturers decided to position it this way in single PCIe 4.0 x16 gen4 mobos.

 

[Karadjgne]

I don't see an issue. The 'top' slot on the motherboard still puts the 'top' of the gpu in front of the psu shroud, so should clear it, the 'height' of the gpu extending towards the front of the case.

All pcie x16 slots on any motherboard format will use the same 321mm cutout section as the area above the 'top' pcie x16 slot is the same for atx, mITX, mATX.

 

[nick1232]

I don't see an issue. The 'top' slot on the motherboard still puts the 'top' of the gpu in front of the psu shroud, so should clear it, the 'height' of the gpu extending towards the front of the case.

All pcie x16 slots on any motherboard format will use the same 321mm cutout section as the area above the 'top' pcie x16 slot is the same for atx, mITX, mATX.

Imagine 318 mm videocard with extra cooling board on its backplate. Even if you manage to put it in here (what perhaps will cause little stress due to strict contact of backplate with PSU shroud) its third cooler will not be able to work effectively, it will be half covered by PSU shroud. If it is in the middle of a section of HDD shroud it is OK, it has enough room for airflow, but it seems there is no single PCIe 4.0 x16 gen4 mobo which positions it's PCIe 4.0 x16 gen4 in here. At least I did not find any of them.

 

[Karadjgne]

Why would the gpu have extra cooling on the backplate? All cooling is on the front (underside) facing the front of that case.

 

[nick1232]

Why would the gpu have extra cooling on the backplate? All cooling is on the front (underside) facing the front of that case.

There was misunderstanding. I talked about these cards are wider in all directions than previous generation. Including extra space on a backplate. Do so calculation and you see there is no point to put such card in that slot. You cover third cooler airflow and you have to literally squeeze it in

 

[Karadjgne]

I want to build my new PC with 30XX nVidia card which is usually 300+ mm length.

The RTX3070 is 242mm long. You'd need to move upto a RTX3080 to see 285mm, which will still fit in that top slot. With as short as the pcb actually is, even aftermarket designs should be running around those same lengths.

The assumption of 300mm + cards in AIB partner cards is probably not accurate.

 

[digitalgriffin]

What do you mean by full side? I considered ATX mobo but it does not matter really since position of PCI-e gen 4 is the same everythere I have looked through a dozen of different mobos of different formats, I did some size comparisons, they all copy same chipset pattern and size of how PCI-E gen 4 is positioned next to CPU. But I could miss something, what I try to check. Since mobos with a double PCIe 4.0 x16 gen4 can position second PCIe 4.0 x16 gen4 further from CPU perhaps some manufacturers decided to position it this way in single PCIe 4.0 x16 gen4 mobos.

The closer the pcie slot to the cpu, the cleaner the signal. Its designed that way for a reason.

X570 with multiple pcie 4 slots is your only option. Sorry.

 

[nick1232]

The RTX3070 is 242mm long. You'd need to move upto a RTX3080 to see 285mm, which will still fit in that top slot. With as short as the pcb actually is, even aftermarket designs should be running around those same lengths.

The assumption of 300mm + cards in AIB partner cards is probably not accurate.

Asus Strix and similar designs are 300+, I considered 3090 as well.

 

[nick1232]

The closer the pcie slot to the cpu, the cleaner the signal. Its designed that way for a reason.

X570 with multiple pcie 4 slots is your only option. Sorry.

There is ASUS ROG STRIX B550-E GAMING mobo with dual slot which is middle priced. Not exactly what I have wanted but taking into account all pros and cons including price for most of good 570 mobos it could be a good compromise. Thank you for an advice anyway

 

[SkyNetRising]

Get mATX board + PCIE extender.

 

[nick1232]

Get mATX board + PCIE extender.

Do you find those things safe? I will check that option as well thank you but it is kinda scary, all mobos builders place sealed in lanes closer to CPU, when that flexible device is extended that much and says it offers stable performance, I really doubt it performs well. But I do check it did not come to my mind

 

[SkyNetRising]

I really doubt it performs well.

No reason to worry about that.

View: https://www.youtube.com/watch?v=QtoagBoelsU

View: https://www.youtube.com/watch?v=q5xvwPa3r7M&feature=youtu.be

 

[digitalgriffin]

There is ASUS ROG STRIX B550-E GAMING mobo with dual slot which is middle priced. Not exactly what I have wanted but taking into account all pros and cons including price for most of good 570 mobos it could be a good compromise. Thank you for an advice anyway

Warning: that middle second slot is pcie 3 not 4. Thats what you are paying for with x570! more pcie 4 slots. Only the closest slot gets pcie 4. Those lanes call me straight from the cpu. The rest of the high speed cpu lanes are reserved for the chipset. And only x570 handles those pcie4 speeds

 

[digitalgriffin]

No reason to worry about that.

View: https://www.youtube.com/watch?v=QtoagBoelsU

View: https://www.youtube.com/watch?v=q5xvwPa3r7M&feature=youtu.be

I cant watch the video right now but did they expressly test that it was running at 4.0 speeds?

I believe the POST process Pcie4 auto negotiates to lower speeds if not stable unless its somehow forced. Then it just wont boot at all. The signal degrades quickly with distance. Each added connector uses different materials at the finger points which causes subtle changes in resistance. This causes reflection ot blurring of the "signal eye"

 

[nick1232]

Warning: that middle second slot is pcie 3 not 4. Thats what you are paying for with x570! more pcie 4 slots. Only the closest slot gets pcie 4. Those lanes call me straight from the cpu. The rest of the high speed cpu lanes are reserved for the chipset. And only x570 handles those pcie4 speeds

Look at scheme it says 2 x PCIe 4.0 x16 SafeSlots (x16, x8/x8) [CPU]

 

[SkyNetRising]

I cant watch the video right now but did they expressly test that it was running at 4.0 speeds?

PCIE 4.0 will not work over PCIE extender (most likely). You'll have to set PCIE speed to PCIE 3.0.
For graphics card this doesn't matter really.

 

[digitalgriffin]

Look at scheme it says 2 x PCIe 4.0 x16 SafeSlots (x16, x8/x8) [CPU]

If you are running 8x/8x then you are running the same data rate as 16x in a single lane. You might as well get pcie3 as each slot is only getting half the available bandwidth.

 

[digitalgriffin]

PCIE 4.0 will not work over PCIE extender (most likely). You'll have to set PCIE speed to PCIE 3.0.
For graphics card this doesn't matter really.

I agree. Unless you are running a low vram card it doesn't matter. Maybe when direct storage becomes available (ssd straight to gpu for texture decompress)

The author kind of wants pcie 4 for his 3080.

This is the first mb I've seen that allows a split of the cpu pcie lanes though. That's a "gutsy" move given degradation issues. I mean even Intel struggled getting pcie 4 up and running. But that might be power related.

 

[nick1232]

If you are running 8x/8x then you are running the same data rate as 16x in a single lane. You might as well get pcie3 as each slot is only getting half the available bandwidth.

I'm gonna run single card but with second PCI-E x16 gen.4 extension. As I understand this particular design those slots designed for SLI/CrossFire are equal if they are used separately and work as gen 4, there is gen 3 slot next to them and that copies similar design in many other boards.

 

[digitalgriffin]

I'm gonna run single card but with second PCI-E x16 gen.4 extension. As I understand this particular design those slots designed for SLI/CrossFire are equal if they are used separately and work as gen 4, there is gen 3 slot next to them and that copies similar design in many other boards.

Can you guarantee all 16 lanes go to the second slot? Every manual i read says put the card in slot 1. Theres usually a bios setting which allows you to split slot bandwidth up. (Like enabling an extra slot at x4/x4 or disabling last slot for a full 8x. This isnt always true as my b450 will auto disable sata slots 2,3 if m2 sata is found.) So read the specs carefully. This sounds like a bit of a risky bet.

Best of luck.

 

[nick1232]

Can you guarantee all 16 lanes go to the second slot? Every manual i read says put the card in slot 1. Theres usually a bios setting which allows you to split slot bandwidth up. (Like enabling an extra slot at x4/x4 or disabling last slot for a full 8x. This isnt always true as my b450 will auto disable sata slots 2,3 if m2 sata is found.) So read the specs carefully. This sounds like a bit of a risky bet.

Best of luck.

No I can't. Thanks for a tip. Perhaps it is an addon for x8 only. I thought they are interchangeable. But that is most probably not the case. Here is what they say about video card configuration.

It is either another case either another mobo. Thank you guys you perhaps saved me ton of money and brain cells...