Mobo Rear Panel USB 2.0 Ports In 2025

[LabRat 891]

Blue ports are typically USB3 5-10gbps, teal USB 3 10-20gbps.
Only very rarely do I have issues using the 3.x type-A ports for OS installs, etc. IIRC, 'top ports' or ports closest to the PS/2 are preferred.
AFAIK, most new mobos completely lack USB 2.0 on the in-built rear I/O. Which, I don't mind. USB3+ signals need the most shielding/integrity, would prefer them be integrated.

Easy fix, but 'too old' of a concept for most to 'have in mind':

I have a bunch of these, gathered over the years; they're still cheap though.
A lot of mobos 'neglect' the top PCI expansion space, anyway. -put it there.

Those are passive converters that run the keyboard or whatever in usb mode despite looking like ps/2 (almost all devices today can do both). Thus, in a true legacy situation without usb drivers they aren't very helpful.

At least I think. Maybe its active, taking another look.

I've used those converters. I *assume* there's some kind of active circuitry inside, as I've had those adapters add considerable input latency.

Really? takes like 45 min start to finish on most configs for me. 25 to 30 of that is updates. Treat yourself to a nice flash drive sometime. You're worth it, and you'll like it.

Even over USB 1.1/2.0, the fastest Win7-11 installer drive I've found, is a cheapie ($4-10) '16GB' M10 Optane stick in a ($20-40) NVME-USB bridging enclosure.

Basically, negates 90+% of the waiting on files to copy over before the installer starts *actually* installing.
Doesn't 'wear out' like 5+ of my flash drives have (that I've been passively collecting for a decade ) and can have different images written to it *very* quickly over USB3.

 

[nomdeplume]

Really? takes like 45 min start to finish on most configs for me. 25 to 30 of that is updates. Treat yourself to a nice flash drive sometime. You're worth it, and you'll like it.

Writing bootable files is probably the larger gain in time where USB speeds are concerned. Hours following to get Windows into shape desired is a one and done pain.
I'm not rushing out to get a USB 4 flash drive for this or the next revision(s) just for the once or twice a year it would get used.

Even over USB 1.1/2.0, the fastest Win7-11 installer drive I've found, is a cheapie ($4-10) '16GB' M10 Optane stick in a ($20-40) NVME-USB bridging enclosure.

That was a solid laugh at something I'd actually consider doing if a cheap enclosure with decent internals existed.

For adding USB 2.0 a simple internal two port adapter is what I'd go with. Easy enough for me to pop the side panel off and a great excuse to make use of the cord securer PCIe panel as a simple passthrough if needed.

Losing 5/10/20gbps ports on back panel to the next highest speed is a total nonissue so long as something functional exists in great enough numbers. What really got me thinking about this was someone posting an addon card to empty slot on front of their case. Rather have numerous 2.0 on rear and solve any need for lots of fast ports in front directly at the port as above with 2.0.

[Begins looking for internal type C male port plug to female connector to see how far above 1000Hz new game controller can be pushed]

 

[natr0n]

The real question is why are the still putting PS2 ports on the I/O panel of motherboards? USB2 ports I can see for USB UART and printer port cables, which USB 2 is still good for.

I have ps2 on my board. Its for windows xp/vintage/older os compatibility. Or not using any usb devices for latency reducing.

Many ways it can help if you have the mind to make use of it.

 

[chrcoluk]

I would like Intel/AMD to make it mandatory there is at least 2 USB2 type A ports on the back panel or to supply a USB2 port bracket with the board, I think its wrong to expect people to buy these brackets to support a standard that has been there decades. Then the board vendors can supply a bracket with USB3 ports if they want to supply more USB 3 ports on their product. New boards also have USB3 headers, not just USB2 headers.

 

[nomdeplume]

I would like Intel/AMD to make it mandatory there is at least 2 USB2 type A ports on the back panel or to supply a USB2 port bracket with the board

Some of the same people who just repackaged the existing chipset as X870.
I'm probably not the only one who could say a mouthful on saleable items and their true known worth. USB 2.0 is not saleable and thus seemed a relatively safe topic.

Thanks to all who have participated thus far.

 

[AusWolf]

I like having USB 2 on the back for compatibility reasons, and use them for keyboard and mouse anyways so.

Same here. USB 3 is cool for external drives, but it's unnecessary for a keyboard and mouse. I've also got a single USB 2 on my front panel that I use for my game controller whenever I play something that needs it.

 

[lexluthermiester]

Noticed that despite having both "blue" and "teal" USB 3 variants I've only recently started to need them. Obviously this is a singular case involving legacy 2.0 era devices that didn't like however the USB 3 spec was implemented on a particular board. It goes much further with kbm (wired) and various sporadically used pluggable devices habitually used in what are both most accessible and offer longest cord reach USB 2.0 ports located on the topmost row. There is also the issue of tranceivers overheating more easily in higher power/bandwidth ports.

Would be curious to hear others thoughts on their continued existence. Current crop of mobo about to be succeeded have a very defined split between full rank of four USB 2.0 in highest position or complete absence of them anywhere on the back panel.

I still use the USB 2.0 ports I have for KB&M and anything else that doesn't need faster bandwidth. Latency has never been an issue so it really is just a case of "what goes where" based on bandwidth needs.

The real question is why are the still putting PS2 ports on the I/O panel of motherboards? USB2 ports I can see for USB UART and printer port cables, which USB 2 is still good for.

PS/2 Keyboards are useful for certain kinds of testing and debugging as keyboard inputs are IRQ based and don't always freeze up when the rest of the system, USB included, does.

 

[chrcoluk]

Same here. USB 3 is cool for external drives, but it's unnecessary for a keyboard and mouse. I've also got a single USB 2 on my front panel that I use for my game controller whenever I play something that needs it.

List of all my currently connected devices.

Work fine on USB 2
Keyboard
Mouse
Printer
Microphone - Front
Xbox360 Controller - Front

Require USB 3 for optimal performance
Elgato HD 60 X capture device. - This is the only device on my back ports that needs USB 3.

Thats it, I will however occasionally connect things like SSD's over USB 3, my phone over USB 3, or USB sticks over USB 3. All these use my front case USB 3 ports when I use them. I used my PS4 controller when using RPCS3, of course thats fine on USB 2.

My case for reference has 4 front USB ports, 2 are USB 2 and 2 are USB 3.

 

[Dr. Dro]

The real question is why are the still putting PS2 ports on the I/O panel of motherboards? USB2 ports I can see for USB UART and printer port cables, which USB 2 is still good for.

Generally, they aren't. Only extreme motherboards still seem to carry true PS/2 ports, and the true reason for that is legacy benchmarking.

 

[lexluthermiester]

and the true reason for that is legacy benchmarking.

And for low-level hardware programming/debugging. Trust me on that one.

Edited to add info.

 

[eidairaman1]

I couldnt use a keyboard in proxmox until it was plugged into a USB2 port or a PS2 port.

A USB3 only system might have yielded me powerless to use any of my wired keyboards on the system.

The only devices I know off in existence that require USB3 levels of bandwidth are capture devices and fast external storage devices, so we have to be careful to avoid making everything USB3 just because it looks good on paper, the vast majority of USB devices dont need USB3 levels of bandwidth.

Same story with PCIE, look at gpu use.

I have ps2 on my board. Its for windows xp/vintage/older os compatibility. Or not using any usb devices for latency reducing.

Many ways it can help if you have the mind to make use of it.

B550 Steel Legend has 1 combo Personal System 2 Port.

 

[Vario]

I've found the USB 2 to generally be more reliable so I usually plug my mouse and keyboard into them.

Blue ports are typically USB3 5-10gbps, teal USB 3 10-20gbps.
Only very rarely do I have issues using the 3.x type-A ports for OS installs, etc. IIRC, 'top ports' or ports closest to the PS/2 are preferred.
AFAIK, most new mobos completely lack USB 2.0 on the in-built rear I/O. Which, I don't mind. USB3+ signals need the most shielding/integrity, would prefer them be integrated.

Easy fix, but 'too old' of a concept for most to 'have in mind':
View attachment 365749
I have a bunch of these, gathered over the years; they're still cheap though.
A lot of mobos 'neglect' the top PCI expansion space, anyway. -put it there.


I've used those converters. I *assume* there's some kind of active circuitry inside, as I've had those adapters add considerable input latency.


Even over USB 1.1/2.0, the fastest Win7-11 installer drive I've found, is a cheapie ($4-10) '16GB' M10 Optane stick in a ($20-40) NVME-USB bridging enclosure.

Basically, negates 90+% of the waiting on files to copy over before the installer starts *actually* installing.
Doesn't 'wear out' like 5+ of my flash drives have (that I've been passively collecting for a decade ) and can have different images written to it *very* quickly over USB3.

I use that type of product a lot.

 

[micropage7]

I've found the USB 2 to generally be more reliable so I usually plug my mouse and keyboard into them.


I use that type of product a lot.

yeah, some cases wireless mouse/keyboard works better on usb 2.0, i dunno what causing this one but having usb 2.0 still a nice feature

 

[TheLostSwede]

You are addressing a side topic bound to come up. In theory if your mobo lacks 2.0 and only 2.0 an easy solution is available. Unless you are already lane constrained or...

What are you talking about?! There's no "lane constraint" for USB 2.0, you simply get a bunch of ports provided by the chipset and then it's up to the motherboard maker to implement those.

I'm very flexible on the wide range of related spatial/technical/manufacturing choices, but equally ready to steer things back towards anyone being able to comment on back panel USB 2.0.

Honestly, I don't get your thread and your complaints at all. You seem to have a very poor understanding of how USB works and are complaining about something that isn't an issues.

There's a reason to prefer USB2 connectors to USB3 connectors, at least when it comes to USB Type A connectors. The USB2 ones are simply more durable. One of the reasons is that they had to split the contact pads to make room for the extra lanes, so there's a lot more wear on those contacts. I honestly do not know how durable USB Type C is compared to USB Type A, however.

USB hardware - Wikipedia

en.wikipedia.org

Honestly, I have never had a single USB port break on a motherboard. On cables, sure, even on the odd USB drive, as some of them are just all plastic, but on a motherboard, not a chance.

 

[DaemonForce]

USB ports can break for any or no reason.
Physically? Not likely but the chance is there.
Logically? Hell yeah. The firmware/BIOS and drivers are all over the place with each board.
To what end? I experimented with this by writing off presence of USB 2.0 on the I/O plate as a red flag.

In 2017-2018 I was on and off experimenting with VR hardware that was having consistent out of box tracking issues directly related to USB connectivity and bandwidth.
This is the panel of my Biostar TA-970 board:

Dual PS/2, 2x USB, 2xUSB, 2xUSB3, 2xUSB and 1GbE Ethernet, audio kit.

In 2018 I switched up to a Gigabyte GA-970A-DS3P to deal with these issues and for whatever reason, it worked out fine. Here's the panel:

Dual PS/2, 2xUSB, 2xUSB, 2xUSB3, 2xUSB and 1GbE Ethernet, audio kit.
Doesn't seem to have any issues or anything out of the ordinary.

See a difference? Neither do I.

Picked up the X570 TUF a year later and made the jump to Ryzen:

2xUSB3.2g1 and PS/2, USB3.2g2 Type C and 2xUSB3.2g1, HDMI and DP, BT5 and Wi-Fi, 2xUSB3.2g2 and 1GbE Ethernet, audio kit.

Once in a while I get recognition issues with some connected devices in some of the USB ports. The bandwidth is all there but the driver has issues.
I don't have any problems right now but almost nothing is connected.

So what's the lesson? No idea. I've opted for a USB 2.0 PCI expansion to make use of the mobo headers.
I'm starting to get to the point where I run out of ports when doing a distribution project and the extenders don't help.
The devices need separate controllers and there's just no better way because I don't get to dig into PCI-E lanes anymore.

An unusual W for Gigglebyte and a weirder W for Asus I guess.

 

[TheLostSwede]

Once in a while I get recognition issues with some connected devices in some of the USB ports. The bandwidth is all there but the driver has issues.
I don't have any problems right now but almost nothing is connected.
View attachment 365800

I can guess what the issue is with that board, the GL850 USB 2.0 hub that shows up as a generic USB hub.
It's a POS, it's been causing issues for years and is the most commonly used USB 2.0 hub due to cost.
If you get something like USB Tree View, USB View or some other USB bus scanning software, you can also see how your USB devices are connected and what "hidden" devices there are.
Yes, my motherboard has one too... I only have one device connected to it, as that seems to avoid any issues.

 

[SL2]

Among the new X800 boards I found this, it actually surprised me. (ASRock X870 Pro RS)

But yeah, out of 28 products, this is what I found.

 

[xtreemchaos]

i feel for you bud, i do astro imaging and my ccd camera will only run on usb 2 or lower so im stuck with using it with a 7 year old laptop or my xeon x99 rigg. the camera is very astro modded for taking pics of sunspots and it would be hard to get something newer without spending a lot of money.

 

[nomdeplume]

What are you talking about?! There's no "lane constraint" for USB 2.0, you simply get a bunch of ports provided by the chipset and then it's up to the motherboard maker to implement those.

"You have run out places to put things" or more likely given the timing of this discussion you are actually lane constrained on your new mobo. So much so there was no room left for USB 2.0.

Honestly, I don't get your thread and your complaints at all. You seem to have a very poor understanding of how USB works and are complaining about something that isn't an issues.

Your choice to interpret thread as complaints and issues - timing played a part in what I'll admit was a (very polite) minor protest towards implication in comment above. There was genuine interest if other members had decided to let USB 2.0 go the way of USB 1.0. Which does not seem to be the case.

I wonder if you might not be fully appreciating the need to add something that could be supplied on the motherboard is seen as an issue, not a solution. Especially when alternatives that don't get used arrived in their place.

 

[TheLostSwede]

Your choice to interpret thread as complaints and issues - timing played a part in what I'll admit was a (very polite) minor protest towards implication in comment above. There was genuine interest if other members had decided to let USB 2.0 go the way of USB 1.0. Which does not seem to be the case.

USB 1.x had inherent issues, like being too slow, especially the low speed mode at 1.5 Mbit, although a lot of devices today still ship with full speed mode at 12 Mbit, but they're usually USB 2.0 compliant, as USB 1.x is missing support for a lot of things that USB 2.0 added. USB 1.x (1.1 was far more common than 1.0 for that matter) was a bit of a mess compared to USB 2.0. Considering USB 2.0 is more or less "free" to add for the motherboard makers, as all they need are the pin headers that costs a few cents, I doubt USB 2.0 will disappear any time soon, even tough you might not find the ports as par of the I/O at the rear of the motherboard. It's also seemingly used for more and more things internally in a PC, such as a control interface for fan and RGB controllers and what not, so it's not going to go away, as for those type of things, there are no benefits to go USB 3.x.

I wonder if you might not be fully appreciating the need to add something that could be supplied on the motherboard is seen as an issue, not a solution. Especially when alternatives that don't get used arrived in their place.

Have you considered that the rear I/O only has so much space? I guess you've also missed the other people on this forum asking for all USB-C ports on their motherboards, who don't want any USB-A connectors at all? People have different needs/wants and this is partly why there are so many different motherboard versions.

What I largely see here are complaints from people that don't quite seem to understand how USB works and why there are some potential issues. Being the only person I know of, that tested 90% of all the USB 3.0 host controllers when USB 3.0 was the hot stuff (TI was the only one I couldn't get hold of and I admittedly didn't test Apple hardware), I can tell you that the implementation varies quite a bit between the various chip makers. At the time, AMD had the absolut worst implementation in their A55 chipset, it was dogshit to put is simply. I tried to talk to their USB 3.0 PM, as he turned up at an AMD event in Taipei that I attended and he refused to talk to me and simply acknowledged that he'd seen my test and walked away.

Keep in mind that the USB-IF consists of over a 1000 companies, of which about a dozen are in charge of defining the standard and if you've ever been to a standards organisation meeting, you'll know that everyone think they're right and everyone else is wrong in how something should be done. As such, no single implementation is going to be identical and that's why there are issues, just as with things like WiFi, Bluetooth and what not where there are multiple strong players that want to be in charge.

What you might blame on your motherboard/chipset might actually be a device that is flawed and doesn't adhere to the standards as well, as most devices has some shitty 8-bit MCU that barely has enough compute power to run the USB protocol. It's used because it's literally free to implement into a chip, but instead we get sub-par hardware. In fact, I know of a company that ended up having to fire their IC design engineer, as he screwed up the USB implementation twice, using an 8-bit MCU design, which meant two wasted tape-outs which is a lot of money for nothing. The old Intel 8051 from the 1980's is still some kind of text book 8-bit MCU a lot engineers learn to make in university and then they keep using it in new designs.

On top of all this, you have companies trying to hit a price point, such as Genesys Logic, who then ends up making trash. Their GL850 hub controllers are well know for having disconnect issues, so whatever you do, check if your board has one of those, before blaming anything else.

That you don't use USB 3.x is a you problem, as the rest of the world is using USB 3.x and it works just fine. But again, see above, it's not a perfect world and at one point we had something like 10 different companies doing their own different implementation of host controllers alone for USB 3.0. Everyone claimed that their solution was superior for some reason or the other (except AMD), but something like UASP wasn't even supported by many of the first gen USB 3.0 host controllers.

These days I very rarely have issues with anything USB 2.0 or 3.x, but I'm not saying there aren't issues out there. What I will say though is buy quality cables, as cheap cables can be a huge part of the problem, as they cause EMI interference and you can easily cause 2.4 GHz RF devices to stop working if the transmitter is close to a leaky USB 3.x cable transmitting data at 5 Gbps.

 

[Dr. Dro]

B550 Steel Legend has 1 combo Personal System 2 Port.

As I understand it, most if not all of these motherboards that have a combo port have it wired to an USB host controller, which is how the same connector can understand both keyboards and mice. These may share the same mini DIN plug, but the communication protocol of a PS/2 keyboard and mouse are completely different, that being the reason why each had its own port.

True PS/2 ports (that act on native interrupts) are very rare nowadays. Only XOC motherboards and a few business models have them.

 

[TheLostSwede]

As I understand it, most if not all of these motherboards that have a combo port have it wired to an USB host controller, which is how the same connector can understand both keyboards and mice. These may share the same mini DIN plug, but the communication protocol of a PS/2 keyboard and mouse are completely different, that being the reason why each had its own port.

True PS/2 ports (that act on native interrupts) are very rare nowadays. Only XOC motherboards and a few business models have them.

The PS/2 ports are wired to the Super I/O chip.

Super I/O - Wikipedia

en.wikipedia.org

 

[datnoz]

The PS/2 ports are wired to the Super I/O chip.

Super I/O - Wikipedia

en.wikipedia.org

So I manage to find the correct signals on the mobo, I could add "true" PS/2 ports ?

 

[TheLostSwede]

So I manage to find the correct signals on the mobo, I could add "true" PS/2 ports ?

Unlikely. It's not as if the motherboard makers leave unused traces there for you to tap into. Not saying it's impossible, but it'll differ between each and every motherboard.
However, I have seen motherboards in the past that had pin-headers for PS/2 ports, but that was some time ago and not on your typical consumer boards, even if it was common-ish on consumer boards for a while too.

Here's a datasheet for a typical Super I/O chip from ITE.

ITE-SuperIO/IT8786E-I_B_V0.2.pdf at master · huchanghui123/ITE-SuperIO

X86 Linux ITE SuperIO GPIO Control. Contribute to huchanghui123/ITE-SuperIO development by creating an account on GitHub.

github.com

 

[nomdeplume]

A fairly large cross section of the membership replying to any thread is generally considered to have contained some worth.

I don't hate USB numbers higher than two. Using an entire breath to get out the full name of a port that includes it's theoretical speed, signal capabilities, and power delivery has gotten to be a bit much. They came out pretty hot and fast with not much staying power and a lot of internal conflicts. A lot of e-waste resulted from uneducated or professional consumers on either ends of the tech spectrum. Enough negatives surround them to be unavoidable in discussions.

Motherboard manufacturers do seem to try to bring out a variety of layouts that fit most needs. Back panel D-SUB and PS/2 specced models with no type C or 20gbps ports on mid to high level chipsets included. To be fair we are mostly talking about USB implementation on gaming or power user builds altering older technologies outside of the shape we've become accustomed to. The equation with USB 2.0 is changing.