Short answer: no.
long answer: kinda sorta.

It's much easier on (early) server boards with "PCI-E PORT BIFURCATION". it would be simple to install a dumb 16x slot adapter and get four 4x slots. however, all of these cards i've seen, are designed for server racks. and turn the cards perpendicular to the motherboard. Universal ones are super rare/expensive.

new consumer motherboards (pcie 3+) tend to have bifurcation now, this is for NVME drives or external video cards.

if you don't have bios support for bifurcation, you will need a more intelligent solution that will likely revolve around an external pci-e chassis. These are insanely expensive compared to the cost of just getting a new motherboard with more suitable pci-e slots.

case in point: https://www.onestopsystems.com/desktop-pcie-enclosures

my advice is to either choose a different motherboard, or find a new card to install that only takes one slot. Its the only 2 economical options I know about.

Thanks. There is no short answer I can provide here for the reason. The issue sort of boils down to Ubuntu's lousy support for AGP graphics cards starting from about Ubuntu 18.04, especially when using the Unity environment (learned this the hard way). This means I'll need to ditch my AGP card for a PCIe card once 16.04 is out of extended support (April 2024) and I need to upgrade to 18.04.

To accomplish this, I would need to ditch my Adaptec 6805T x8 PCIe RAID card, which does 600+ MByte/s on SSD drives, for some PCIe combination card which has SATA 3.0 + USB 3.0. My tests show that Read/Write w/SSD on this ASM1061-based combination controller card are only 375 MB/s read and 310 MB/s write. I'd then put a PCIe x1 grahpics card into the x1 slot and remove the USB 3.1 card currently there. It is hard to give up that Adaptec RAID card for something half the speed though. The other solution is to keep the Adaptec RAID and use a PCI-to-PCIe USB 3.0 card, but that will be darn slow compared to running USB 3.1 on PCIe.

Hence why I'd like to break-out the x16 slot into two x8 slots. From your response, sounds like there isn't a pre-packaged internal solution to make two half-height x8 slots from one x16 slot. I don't really want to invest the time in a new motherboard when the current one works fine, minus the above noted limitation coming in 2024.

feipoa wrote on 2021-04-14, 00:12:

I don't really want to invest the time in a new motherboard when the current one works fine, minus the above noted limitation coming in 2024.

depending on if your motherboard supports bifurication a simple bifurication riser would work, but a new motherboard would probably be the more economical and practical solution.

Searching the AsRock 939Dual-SATA2 manual for "bifurication" or "bifurcation" comes up empty handed. Does that mean it isn't supported?

EDIT: North Bridge: ULi M1695 chipset; South Bridge: ULi M1567 chipset

Like others said, smart move is to get workstation computer instead if vintage enough, will be not that expensive and to keep your goodies. This way you get more PCIe slots using 40 lanes processor, oh! be mindful of low end Xeon processor for that same socket that only supports 28 lanes. Z420 does support ivy bridge processor and supports current Win 10 OSes including XP and Linux likes workstation much too.

If your raid card is 4 drives, then you can use one 5.25" bay with 4 spaces for the SSD drives or use 2 bays if you are running 8 SSD drives (that expensive!). 😀

If you are in USA, roughly 300 dollars Z420 PC will net you about 32GB (8pc ECC unregistered, DDR3-1866), or 64GB ram registered ECC of 4x 16GB DDR3-1866 modules (I have done that and does work), Z420 with xeon Xeon E5-1620 v2 (socket 2011, 40 lanes, 10MB, 4 cores for total of 8 threads, 600W PSU but can work with 250-280W GPU no problems and is quiet. And memory bandwidth is high due to 4 channel memory rather than dual channel.

If the intel chipset states x16, and x8 or x4 and x4 that what you get for example.
On typical processors based on sandy bridge and later consumer class you will only get up to 1x16, 2x8, 1x8 & 2x4 which I extracted from i7-3770K intel datasheet but there is usually x4 more from the chipset. Not very practical. Xeon E3 processors that uses socket 1155 entry level workstations are 20 lanes which is: 1x16 & 1x4, 2x8 & 1x4 or 1x8 & 3x4

Check the chipset datasheet and processor datasheet. Typically the high end chipset like x58 has more lanes but boards are north of 300 dollars used.

Thirdly, Not all GPU cards supports x8 mode or less especially vintage ones.

For this reason, look at workstation computers instead. Dell T3610 and HP Z420 are very reasonable for single socket workstations.

Cheers,

Well, you still have 3 years to go if you plan on keeping that system till then.

That is already a really old system and much newer stuff that would suite your needs of having to move to PCIe for video is already pretty cheap.

I've been running the higher end Intel boards for years, starting with x58.

My newest setup is using the ASUS X99E-WS USB 3.1 motherboard which I picked up on eBay for about $100 because the socket had some damaged pins.

I was able to straighten all the pins but one. One broke off and I was only getting triple channel for the RAM. I ended up ordering a new socket from China and used one of the pins as a doner.. trimmed it, and dropped it in the socket where the broken pin was.

Now it works like new.

I have 2 other x99 boards I bought off eBay for super cheap because of bent socket pins. Those two were really easy to fix and are now spare boards.

That being said, I wouldn't pay over about $100 for an x58 or X79 board and eBay prices are super crazy right now.

If AMD keeps going how they are now, anything from these last few years should be cheap as chips by that then.

I’m not upgrading the motherboard. I would rather work with the existing limitations.

You're kinda out of luck then unless you get an external enclosure.

What OS are you running?

cyclone3d wrote on 2021-04-14, 01:32:

You're kinda out of luck then unless you get an external enclosure.

What OS are you running?

feipoa wrote on 2021-04-14, 00:12:

There is no short answer I can provide here for the reason. The issue sort of boils down to Ubuntu's lousy support for AGP graphics cards starting from about Ubuntu 18.04, especially when using the Unity environment (learned this the hard way). This means I'll need to ditch my AGP card for a PCIe card once 16.04 is out of extended support (April 2024) and I need to upgrade to 18.04.

Oh... Hah.... Duurrrrrr.

I mean I personally have a dual socket 1151 machine that runs my nas. It was only $100 plus shipping. Lets me run 24x 2.5" drives effortlessly.

Yes, I know what you have works, but there comes a time when your time and effort just isn't worth it. This might be that time.

If you are using this hardware as a NAS, then a newer board will let you run something more suited for that task. In this case, TrueNas. Formally known as Freenas.

lol, I wouldn't have expected such push back on this forum. I'm not upgrading the system just to save an Adaptec RAID controller, when everything else otherwise works for my needs. I'd rather,

a) go RAID-less with the SATA 3.0 + USB 3.0 combination card (which is x2) in the x16 slot and use a PCIe x1 graphics card in the other slot.
b) continue with the existing setup and ditch Unity for the GNOME3 desktop environment - and deal with the few graphics bugs
c) bug the appropriate linux developers to fix bugs in b)
d) keep the RAID (x16), use x1 graphics, and use a PCI-to-PCIe adapter for USB 3.0 (still need to test throughput on this w/SSD)
e)Perhaps a PCI graphics card , the GT610, will fix the Ubuntu 18.04 bugs. Not like there's any gaming on this system.

There are some small trade-offs which I prefer over upgrading the system entirely. I was just wondering about a PCIe x16 splitter, not wanting to discuss full system upgrades. Since something called "bifurcation" is needed to split this up and I don't know if my system supports this (unlikely), it seems I'll be revisting options a-e. Wouldn't the splitter work in the same way that combination cards are able to split up the lanes? The SATA 3.0 + USB 3.0 card for examples, uses 2 lanes, so some hardware must be handling this.

Is there even a half-height PCIe x16 splitter I can test out that is not external?

feipoa wrote on 2021-04-14, 22:48:

lol, I wouldn't have expected such push back on this forum. I'm not upgrading the system just to save an Adaptec RAID controll […]
Show full quote

🤣, I wouldn't have expected such push back on this forum. I'm not upgrading the system just to save an Adaptec RAID controller, when everything else otherwise works for my needs. I'd rather,

a) go RAID-less with the SATA 3.0 + USB 3.0 combination card (which is x2) in the x16 slot and use a PCIe x1 graphics card in the other slot.
b) continue with the existing setup and ditch Unity for the GNOME3 desktop environment - and deal with the few graphics bugs
c) bug the appropriate linux developers to fix bugs in b)
d) keep the RAID (x16), use x1 graphics, and use a PCI-to-PCIe adapter for USB 3.0 (still need to test throughput on this w/SSD)
e)Perhaps a PCI graphics card , the GT610, will fix the Ubuntu 18.04 bugs. Not like there's any gaming on this system.

There are some small trade-offs which I prefer over upgrading the system entirely. I was just wondering about a PCIe x16 splitter, not wanting to discuss full system upgrades. Since something called "bifurcation" is needed to split this up and I don't know if my system supports this (unlikely), it seems I'll be revisting options a-e. Wouldn't the splitter work in the same way that combination cards are able to split up the lanes? The SATA 3.0 + USB 3.0 card for examples, uses 2 lanes, so some hardware must be handling this.

Is there even a half-height PCIe x16 splitter I can test out that is not external?

At least personally. my pushback comes from personal experience. I've been there. I've done it. I would like nothing more than to turn one of my old p-pro servers into a network storage. But the reality of the hardware, means I cant have everything I want.

A) 3.0 pci-e cards are usually x1. it might use an x2 slot for power, but I think its only a 1x. And a series of usb/sata adapters can be an option. I dont see it as a STABLE option.
B) Honestly this would be my choice, at least at the moment.
C) I'm not going to hold my breath there, but I've been running Debian for school. Maybe that will work better?
D) I know there exists a standard pci to 3.0 card exists. I think its obvious what bottleneck would be.
E) also a good choice, probably better than B

I'm curious, what motherboard do you have, and what would be a "perfect" replacement?

luckybob wrote on 2021-04-14, 23:27:

I'm curious, what motherboard do you have, and what would be a "perfect" replacement?

feipoa wrote on 2021-04-14, 00:38:

Searching the AsRock 939Dual-SATA2 manual for "bifurication" or "bifurcation" comes up empty handed. Does that mean it isn't supported?

EDIT: North Bridge: ULi M1695 chipset; South Bridge: ULi M1567 chipset

I'm not swapping the board.

luckybob wrote on 2021-04-14, 23:27:

A) 3.0 pci-e cards are usually x1. it might use an x2 slot for power, but I think its only a 1x. And a series of usb/sata ada […]
Show full quote

A) 3.0 pci-e cards are usually x1. it might use an x2 slot for power, but I think its only a 1x. And a series of usb/sata adapters can be an option. I dont see it as a STABLE option.
B) Honestly this would be my choice, at least at the moment.
C) I'm not going to hold my breath there, but I've been running Debian for school. Maybe that will work better?
D) I know there exists a standard pci to 3.0 card exists. I think its obvious what bottleneck would be.
E) also a good choice, probably better than B

A) There are USB 3.2 chipsets which can do 2-lane now, but yes USB 3.0 appears to be limited to 1-lane. The USB 3.0/SATA 3.0 hybrid card I mention has a x4 connector with two lanes wired up for data. Originally I thought it used one lane for USB and one for SATA, but I'm not sore sure any longer after I tested the SATA 3.0 controller with a Samsung 870 EVO SSD - it benches 374 MBytes/s for read and around 304 MB/s for write. My board has PCIe 1.0a, which is limited to 250 MByte/s once uncoded.

There are some 2-lane non-RAID controller cards, like the ASM1062 and ASM1166, which should do 500 MBytes/s on my system in non-RAID mode, but I have been unable to find them on a combination card with USB 3.X. If I could find one of those, I'd ditch the Adaptec RAID.

B) It will be hard to ditch Unity as all other computers in the house run it. I tried to get used to GNOME3 but couldn't. I

D) Startech makes a conventional PCI USB 3.0 card, but the linux kernel doesn't support it and Startech refused to provide a driver for Linux. I had been in contact with them already. I guess the issue is the PCI bridge chip that it uses. That's why I suggested using a PCI-to-PCIe adapter with a half-height USB 3.0 card. I haven't benched this with an SSD yet, but even if it can do the full 133 MBytes/s, I'm not sure if that would be satisfactory. On PCIe 1.0a, x1, w/USB 3.x card, I get around 185 MByte/s. Not sure why it isn't higher, PCIe 1.0a x1 should do 250 MBytes/s uncoded.

E) Might take some hackery to get this working. I did a quick test with a PCIe x1 card with the existing setup w/Ubuntu 16.04 and the system wouldn't boot. Perhaps another bridge chip issue. I don't know.

I wish there were more combination PCIe cards, one which uses 2-lanes for SATA 3.0 and 2-lanes for USB 3.2 would be nice, but it seems PCIe 1.0a was kind of forgotten with these upgrades. 1-lane is mostly sufficient if using PCIe 2.0 and that seems to be the basic target of these upgrade cards and their included logic chips.

Where does x1 card went to which slot? x16 slot or the x1 and was that a GPU?

There are much newer GPU cards that can be run as x1 (test GPU card on open ended x1 computer slot before cutting the PCIe connector down to x1 and Matrox did make G550 cards with x1 PCIe.

Cheers,

The motherboards has:
PCIe 1.0a x1
PCIe 1.0a x16
AGP 8x
three conventional PCI slots

Currently setup:
PCIe x1 = USB 3.0
PCIex16 - Adaptec RAID 6805T x8 card
AGP 8x = Nvidia GeForce 6600GT
PCI = Intel Pro 1000MT

I tried a GeForce 6800GT in the AGP slot, which is able to run my 1080p videos from my phone/digicam a bit better, but there is some screen tearing which occurs, like the screen gets all cut up into triangles. I'm not sure why. It happens after about 2 minutes of uptime in Ubuntu, but had no issues in WinXP. That's why I'm using the 6600GT. 1080p videos are almost perfectly smooth, but I suspect the PCIe bridge adapter on the board is causing some bottleneck. I have a non-GT 6800 I want to try, but it has taken FOREVER to get here from Russia.

I've tried the AMD 4350 and 4650, but they have this weird issue which causes horrible stuttering when scrolling files in the file manager (e.g. caja, nautilus, etc) and Firefox, even with firefox HW accel. disabled. The scrolling in the file manager made me downgrade to the 6600GT. AMD proprietary drivers aren't supported in Linux kernel 4.x, so I have to use the open source AMD drivers. If I use a GT710 or GT740 in the PCIex16 slot, there are no graphic issues whatsoever.

Obviously, getting the open source AMD driver fixed for the 4650 to fix those scrolling staggers is another option, but the person in charge of the driver will have to care enough to want to fix this. Reading the forums for a solution to this resulted in zilch.

Anything GF4 and older just don't run on Ubuntu 16.04, at least not on my system.

I have a GT710 in the PCIe x1 flavour, but I'm still stuck with the above A-E limitations. I suppose I could give up USB 3.0 entirely and backup my system by turning ot off and plugging a SATA drive into the Adaptec 6805T, runnig a clone, pull the drive out, putting the drive in the safe, and boot back up. But I don't want to have to turn it off at each small backup. This RAID controller doesn't seem to support hot plugging, at least not when I did the test.

Why are you so against changing the motherboard? You are just making it needlessly difficult for yourself.

cyclone3d wrote on 2021-04-15, 02:48:

Why are you so against changing the motherboard? You are just making it needlessly difficult for yourself.

lol, I think you're in the wrong forum. If the difficulty bothered me, I'd change the board. It doesn't.

feipoa wrote on 2021-04-15, 03:31:

cyclone3d wrote on 2021-04-15, 02:48:

Why are you so against changing the motherboard? You are just making it needlessly difficult for yourself.

🤣, I think you're in the wrong forum. If the difficulty bothered me, I'd change the board. It doesn't.

It just seems to me like you are wanting to run the updated OS that is dropping support for AGP. Does this even mean that it will stop working? I'm not up on how Linux supports / doesn't support stuff in the kernel.

To top it off, you have like 3 years before this becomes a problem. I don't see any reason to start fretting over it now. For all you know, the motherboard, video card, or RAID card will completely die before then.

In any case, even though I really like retro / vintage computing, but I also take into account what a system is good for. If the OS definitely will not support / work with the hardware I am trying to use, I will use hardware that will work with it.

And if I have hardware that I want to use, I will get a motherboard that will work with the hardware I am wanting to use.

Vintage / retro computing isn't about making things difficult just for the sake of it being difficult.