Flexible PCIe risers

I've read that PCIe 4.0 is backwards compatible. Doesn't that assume the same connector will be used? Otherwise, what's the point?
 
DG25 said:
I've read that PCIe 4.0 is backwards compatible. Doesn't that assume the same connector will be used? Otherwise, what's the point?
Click to expand...

That means you can plug a Gen3 card into a Gen4 slot. But not necessarily a Gen4 card into a Gen3 slot.
 
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I checked into Samtec. Pricing is higher than 3M for 300mm. They are sending me a sample to test, so I'll post when I do that. From website it looks very similar or same as 3M construction.

Waiting on TC&C to get back to me on drawing but quoted good pricing.
 
I agree that gen 3 is overkill, but most users don't want to face a blue screen and have go into the bios and set gen 2. It's a bad first impression.

Im thinking of offering the choice of an expensive gen3 or a mildly priced gen2, and let the buyer decide.

But some of those cheap blue stripe risers are only rated for gen 1, and I've seen some poor soldering under the tape, and no strain relief. So there would still a need to define a quality gen2 riser source.
 
Fyi,
I received a Samtec pcie riser cable as a sample to try in my Mi-6 computer. Cable assy is sturdy and twin axial, but not that flexible. I did an install test and run test. Seemed to work fine, performance wise.
 
Firewolfy said:
I agree that gen 3 is overkill, but most users don't want to face a blue screen and have go into the bios and set gen 2. It's a bad first impression.

Im thinking of offering the choice of an expensive gen3 or a mildly priced gen2, and let the buyer decide.

But some of those cheap blue stripe risers are only rated for gen 1, and I've seen some poor soldering under the tape, and no strain relief. So there would still a need to define a quality gen2 riser source.
Click to expand...

See, I would definitely pay the extra for the option for a 3M cable; in either the MI-6, or in the Hutzy XS…

A tad bit of overkill on such a crucial component of the systems infrastructure cannot be a bad thing…
 
Firewolfy said:
Fyi,
I received a Samtec pcie riser cable as a sample to try in my Mi-6 computer. Cable assy is sturdy and twin axial, but not that flexible. I did an install test and run test. Seemed to work fine, performance wise.
Click to expand...

Good info, thank you! Could you post a picture and maybe a short description that I can just paste into the original post?
 
Here is pic and such I put in the mi-6 thread:

Firewolfy said:
Update time!
Tested a new PCIE riser cable, the Samtec 300mm x16 model.
Samtec%20300mm%20x16%20riser%20overall.jpg


Looks like it has twin axial construction like the 3M with shield over every pair, but about 2mm thick for both cables, and not very flexible. It has clear epoxy over the soldered ends and seems pretty solid as a strain relief:
Samtec%20pcie%20riser%20closeup.jpg


A bit of a challenge to fit it in the case. The top looks good, plenty of cable length:
Samtech%20installed%20top.jpg


But the lower end pcb is a tight fit:
Samtech%20installed%20bottom.jpg

It worked fine and ran at gen 3.0, and no glitches or hangs when I moved the cable around.


Second test: the Noctua NH-L9x65 cpu cooler!

Here is the back of the MB. Getting ready to swap out the Big Shuriken 2 for the x65:
Noctua%20NH-L9x65%20cooler%20swap.jpg




Here is the Noctua 115x backplate installed:
Noctua%20NH-L9x65%20backplate%20install.jpg



Here it is installed. It has that wee little 92mm fan so lots of room around it:
Noctua%20NH-L9x65%20cooler%20installed.jpg


It fit in the the case with about 2mm to spare to the outer wall, so that was about as expected.

I repeated the prime 95 and furmark test I had run on the other coolers. A bit warmer than the Shiriken. Results below with the Noctua in blue and the baseline Shiriken in green:
G1-G7%20results.jpg


EDIT -- Forgot to mention, CPU is unchanged (still i7-6700K), GPU is unchanged (still Gigabyte GTX 1070itx).
Click to expand...
 
I tried this cable these past few days:

https://www.amazon.com/EZDIY-Expres...coding=UTF8&psc=1&refRID=M6R6XK4MKHA6J2B6AMTG

Z4ci7kA.jpg


Which is more or less the same cable as the Thermaltake, and looks to be the same as the ModDIY one.

It's thinner than the generic ones, because the traces all go towards one side of the PCB, meaning the ribbon itself consists of 1 ribbon cable instead 2 like the generic ones.

I measured it at 1mm thickness, vs generic ribbons' 1.6mm thickness.

Observations:

I tried the cable with a GTX 750 Ti and a GTX 970. I've tried many boots, and even tried to reset the CMOS battery to make sure the BIOS settings go back to stock.

With this ribbon, I was able to boot into Windows under "Auto" and "Gen 3" set as the max bandwidth for PCIE in BIOS. This differs from the generic cable that have a hard time booting into Windows with "Gen 3"

However, I was not able to get the cable to actually run at 16x 3.0 thereafter; it ran Furmark and League of Legends at 16x 1.1
This does not differ from the generic cables; whenever the generic cable was able to boot into Windows with Gen 3, GPUZ would report it as running "PCI-E 3.0 16x @ 16x 1.1"

When I reverted the BIOS setting to "Gen 2" max bandwidth, it was able to run at 16x 2.0

Overall, I'm disappointed. I really wanted to use this cable in place of the generic one. But with basically no performance improvements, I cannot justify using it.
 
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Might be the case (no pun intended) that you have the mounting point for the PCIe riser cable on the GPU end able to fit an assortment of common / popular PCIe riser cables…

This would allow the end user / purchaser of the Hutzy XS to source their own cable (…cough… Holy… cough… 3M… cough… Grail… cough…), bringing down the cost of the chassis overall…?
 
Some cables' mounting point overlap but do not match, so that kind of "fit many" design can only do so much.

For example, generics and the one I tried cannot be mounted on the same holes, but are close enough that it's impossible have mounting points for both separated.

In XS, the mounting holes are not simple holes, they are tapped holes for screws. This adds to the difficulty of fitting overlapping mounting points together.

This means that to support multiple cable types, it's easier to just have different SKUs of the middle board, but this adds cost of course.
 
Hahutzy said:
It's thinner than the generic ones, because the traces all go towards one side of the PCB, meaning the ribbon itself consists of 1 ribbon cable instead 2 like the generic ones.
Click to expand...

That is very weird, that would mean that there are about 40 vias to bring the signals to the other side of the PCB, which could hurt signal integrity and the ribbon would have to be of much lower pitch than generic ones are.

Too bad the performance wasn't there, it looks pretty nice and 1mm is pretty good in terms of thickness.
 
LOL…

I like the bottom of the page, with a breakdown of country flags & # of visitors from those countries…
 
I'll add it later, but it seems like this would perform even worse than most generic risers. There are not just four connection points, but six. The signal goes from the motherboard through the PCIe connector through the solder joints through the ribbon connector into the ribbon and then through the ribbon connector through the solder joints through the other PCIe connector out the other side. And the ribbon looks like it's not shielded either, and if it was wrapped in aluminium tape or something, there'd be no way for it to connect to the shield ground on the ribbon connector. I wouldn't trust this riser farther than I can throw it.
 
I have tried the ModDIY/sintech cables. ordered the 2x 19cm and the 2x 30 cm .
I have Gigabyte GTX1070 that I tested with and Supermicro x9dai dual cpu board.
in GEN2 setting only with the 19cm I was able to boot and 3dMark passed the test well.
In GEN3 non of the cables worked. freeze on boot.
the 30cm didnt work stable even in the GEN2 setting on bios. succeeded to boot every 2-3 retries and then froze in windows.
do not recommend at all.
I am returning them to the shop.
Ordered the 3M cables from Digikey, the 50cm are for 86$.
lets hope they will perform as people testify.
 
I'm glad I stumbled across this thread.

I'm ordering a Streacom FC5WS HTPC case, and need a riser for it.

At first I just typed in "flexible pcie riser" in Amazon, and I found a bunch of shady looking parts, one with lots of reviews saying it burned up their motherboard, and the rest with either no reviews, or one perfect 5 star review from someone who has never reviewed anything else.

I'm going to start searching for the ones mentioned above.

Ideally I need something A LOT shorter than the ones in this list. A hard right angle type riser would be ideal, but the manual for the case says to use a flexible riser, and I have no way of knowing if any of the hard right angle ones on the market (from the likes of Supermicro) will fit.

Any recommendations?
 
Zarathustra[H] said:
Ideally I need something A LOT shorter than the ones in this list. [...] Any recommendations?
Click to expand...

In that case, NFC might be able to sell you one of the flexible risers he's using in his S4 Mini Chassis. Not sure how active he is on [H] at the moment, but you can easily reach him on SFFn. You can see pictures of the riser in the thread for his case. Hope that's helpful.
 
iFreilicht said:
In that case, NFC might be able to sell you one of the flexible risers he's using in his S4 Mini Chassis. Not sure how active he is on [H] at the moment, but you can easily reach him on SFFn. You can see pictures of the riser in the thread for his case. Hope that's helpful.
Click to expand...


I appreciate the suggestion. I actually went ahead and ordered one of the 5CM (~2") Sintech ones. Hopefully this will work well, without a floppy ribbon cable all over the place inside my small case.

Unfortunately, now I have to wait for stuff to arrive from China. That's the worst part with all this accessory stuff. Why can't they just warehouse the stuff here for crying out loud. I don't like waiting for the stuff to take the slow boat from China!
 
Zarathustra[H] said:
Why can't they just
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Because distribution chain management is complicated and costly, probably not worth it for sintech. What I find more astounding is that Streacom doesn't stock a fitting ribbon cable themselves. They offer a case that requires it, I would expect them to have the necessary accessories available. They have all sorts of useful stuff for their cases, but apparently PCIe risers aren't important enough.
 
I am pleased to have found this thread. In 2010 I was flustrated with low quality flexible riser card assemblies. They were expensive and caused various faults. Then last year I found the same to be true. The quality appeared to be greatly improved but the system was not reliable and had several fault conditions that cleared when the risers were removed (I purchased three different ones in that project).

So now I will only use PCB riser cards and have experienced no problems on two completed projects.

neil
 
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Good to hear it was helpful! Well, you're still saving a lot of money when going with stiff risers, so there are good arguments to go for those rather than flexible ones.
 
iFreilicht said:
Good to hear it was helpful! Well, you're still saving a lot of money when going with stiff risers, so there are good arguments to go for those rather than flexible ones.
Click to expand...


I would have preferred stiff risers too. Would have been more reliable, and provided more mechanical support to the GPU.

Just couldn't find any that fit right. I know it would have been possible to find one the right height, but it wouldn't have lined up with the right slot on the motherboard.
 
Yeah there are tons of fitment drawbacks with stiff risers due to motherboard manufacturers trying to cram as much IO as possible. The only way to ensure max compatibility is to use a flexible riser or to use a two piece hard riser which reduces speed.

I will say that here in 2017 flexible risers are leaps and bounds above what they were even a year ago across the board, but both li-heat and HDPLEX have risers with amazing performance and so far reliability. ADEX Electronics also makes a really good riser and I used them for the S3 MINI years ago. Their manufacturing capability ensured a riser that still is one of the top performers in 2017 and because of the S3 they can be ordered in custom lengths. Finally check out Ameri-Rack which is another company that I worked with for an industrial project. We only ordered 4x cables for them, but they were high-bandwidth broadcast cards. They performed very well and we had no failures across about 175 units over 3 years.

I hope this helps, and thank you, iFreilicht, for helping the community out with this info.
 
Hahutzy said:
That means you can plug a Gen3 card into a Gen4 slot. But not necessarily a Gen4 card into a Gen3 slot.
Click to expand...

Could it be a return to something similar to the Vesa Local Bus days?

Vlb.jpg


A regular 16 bit ISA slot in the front, and an optional VLB socket behind it. That way the slot could be used for either traditional 8 both or 16 bit ISA or a full length VLB card.
 
Hahutzy said:
Following your success, I changed the speed to Gen2 as well in the BIOS for my Hutzy XS prototype. It is now running flawlessly on the same generic riser that kept failing before.

I'm coming to a hypothesis here, which will suggest that the generic risers are still useful:

1) A lot of people have tried and failed to use generic risers. I think it's safe to say that the issue was their system was trying to run the connection in PCIE 3.0 x16, and the riser cannot provide that speed.

2) I don't know exactly the reason for why it can't do PCIE 3.0 (cable impedance?), but I am quite certain it is not EMI, as in all scenarios where I have failed in using the riser, adding some sort of Faraday cage to the ribbon has not changed the result.

3) When running in Gen2, I have still not had my risers fail on me.
a) In my older test system, I was using a Haswell chip that can do Gen3 (i5-4440S), but my mobo -- Gigabyte H81N -- was only providing PCIE 2.0 (all H81 boards only did PCIE 2.0)
b) When I switched to my Skylake system (i5-6400 + MSI H110I PRO AC), it started failing continuously, until today when I set it to run Gen2 in BIOS
c) All the while, my i5-4440S and Gigabyte H81N have been running in my current workstation build -- Hutzy HS (Hassium) -- with my GTX 980 Ti, and I have not had a problem. This is the system that I do all my gaming / design / rendering / browsing on.

So my hypothesis is this: for any build where it is instructed specifically to run at PCIE 2.0 x16, the generic riser (up to 300mm that I tried) will perform correctly and successfully.
Any failure of performance from using these risers should result in a first-step diagnosis of checking whether the system is running at PCIE 2.0, or is it automatically trying to achieve PCIE 3.0, latter of which will make the riser fail.




Now a follow-up for discussion:

PCIE 2.0 x16 has the same bandwidth as PCIE 3.0 x8. So we have to ask ourselves: Is that enough? Or do we have something to gain from being able to achieve PCIE 3.0 x16?

The current trend on the other side of the playing field is using external GPU enclosures that connect with Thunderbolt 3.
Alienware Amp, Razer Core.. the TB3 connection they use carry a PCIE 3.0 x4 (PCIE 2.0 x8) connection on them, which in itself is another topic of discussion.
But that's half the bandwidth the generic riser provides, and as far as I know, a GTX 1070 can't even saturate the PCIE 3.0 x4 (PCIE 2.0 x8) connection on there. GTX1080 gets close I believe.
It might take a while for a consumer card to saturate PCIE 2.0 x16.

So to sum it up: as far as the state of current technologies is concerned, PCIE 2.0 x16 is way more than enough, especially in the context of SFF builds.
Achieving PCIE 3.0 x16 feels great of course, but it is essentially gaining you zero real life performance.

So if it really is true that the generic riser can handle PCIE 2.0 x16 without fault, to me personally it is quite tempting to settle at that than paying $80 for a cable that adds headroom nothing uses and no performance gain.
Click to expand...



Thanks for all your work.

I am now having the issue that i can't change my PCI-E speed in my gigabyte itx boards bios... it defaults to 3.0 x16
 
Zarathustra[H] said:
I appreciate the suggestion. I actually went ahead and ordered one of the 5CM (~2") Sintech ones. Hopefully this will work well, without a floppy ribbon cable all over the place inside my small case.

Unfortunately, now I have to wait for stuff to arrive from China. That's the worst part with all this accessory stuff. Why can't they just warehouse the stuff here for crying out loud. I don't like waiting for the stuff to take the slow boat from China!
Click to expand...

Did the sintech one work with gen3?

I am in the exact same boat with a streacom case but there is no option to change pci-e speed in the bios (gigabyte).
 
gotbass said:
Did the sintech one work with gen3?

I am in the exact same boat with a streacom case but there is no option to change pci-e speed in the bios (gigabyte).
Click to expand...

Not sure.

My GPU or this build was a GT720 (it's just a little HTPC) and if I remember correctly, the 720 maxes out at Gen2 x8...
 
I've got one of these: http://www.hd-plex.com/HDPLEX-Silicon-PCIEx16-3.0-Flexible-Riser.html

But it's not long enough :( I'm trying to make a lego pc case and have the card flipped over the back of the motherboard like DAN A4 case, but not sure what to do now.

One reason it's not long enough is imo it faces the wrong direction

Will try and explain with diagram:

Fig.1:
It specifically says 1 end is for motherboard, and other end is for GPU, so when you plug it in, the cable goes across the top of the motherboard like i've drawn

Fig. 2: If you try bend it back around the motherboard, it doesnt bend so well because the start of it goes to the right, then has to do a big curve back over, which causes it not to get very far.

Fig 3. If I could plug it in so it faced left instead of right then it could much more easily flow around without doing a big space-wasting curve



Does anyone know if you can get 180degree pci-e adapters/converts ?
 

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Thank you for this topic. That hdplex one looks the best. I want to make a show build so I need the best looking one. The idea is shrinking a full atx build centred around msi x370 titanium board.
I've come across a new pci riser cable from Thermaltake that looks almost identical to the lian li one but it can range up to 1m long.
Would there be a huge loss if I was to use two of those hdplex together for extra length?
 
Nighthuntertauren said:
Would there be a huge loss if I was to use two of those hdplex together for extra length?
Click to expand...

I tried that, it didn't work. It seems like there's huge signal integrity loss in the physical connections, much more than in the ribbon.

So, with the way the HDPLEX riser is designed, by adding one more riser, you add two physical connections instead of just one. So with two risers, you have a similar loss as if you chained four normal ones together, and it seems like PCIe can't handle that. You can shoot HDPLEX an email though and ask what a custom length would cost. If you're indeed going for show build and have money to spare, that might be a good way to do things.
 
Wonder does 3M come in black? Otherwise the Lian-li 380 mm my other option.
 
Bladestorm said:
Any thoughts on this riser?

http://adtlink.com/index.php/photo/index/id/10.html

There's not much info there, but if you translate this page it helps.

https://world.taobao.com/item/54989...1.14.87.ebb2eb2SAwRC8&ns=1&abbucket=17#detail

My biggest concern is this statement -

"Adaptation graphics: GTX1080ti high-end graphics card, firepro w7100,radeon pro wx5100, quadroK1200 professional graphics card, GXT1050ti need to welding standby power, please note."

Any idea what that means?
Click to expand...
The statement:"GXT1050ti need to welding standby power, please note" Did you see the space for 4 pin connector on the riser?
GTX1050ti is powered by PCI-E slot only, the ribbon can not provide enough current, so you need to solder 12v wires to power the gtx1050ti.
 
fishell said:
The statement:"GXT1050ti need to welding standby power, please note" Did you see the space for 4 pin connector on the riser?
GTX1050ti is powered by PCI-E slot only, the ribbon can not provide enough current, so you need to solder 12v wires to power the gtx1050ti.
Click to expand...

So there shouldn't be a problem with my 1080 Ti?
 
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