TIP: Always put high-Hz keyboard and high-Hz mouse on SEPARATE DEDICATED USB CHIPS.

Everything about latency. Tips, testing methods, mouse lag, display lag, game engine lag, network lag, whole input lag chain, VSYNC OFF vs VSYNC ON, and more! Input Lag Articles on Blur Busters.
b0t
Posts: 101
Joined: 16 Jan 2017, 00:10

Re: TIP: Always put high-Hz keyboard and high-Hz mouse on SEPARATE DEDICATED USB CHIPS.

Post by b0t » 10 Apr 2024, 13:23

Chief Blur Buster wrote:
16 Oct 2020, 00:29
Houston, we have a problem.

Especially with 4000 Hz keyboards and 8000 Hz mice being used simultaneously.

I just helped someone solve a high-Hz USB performance interference problem between two high-Hz USB devices:

Problem: High-Hz poll performance interference between 1000 Hz keyboard + 1000 Hz mouse
MaxTendency wrote:
12 Oct 2020, 16:35
While I'm pretty convinced that 8k hz mouse polling is going to be not only noticeable but also impactful , I'm starting to wonder how much keyboard polling will affect this. High keyboard polling has known to destabilize the mouse polling and vice versa.

Image
For example this is a 1khz mouse polling on an optimized setup with a 125hz keyboard. As you can see the variance is quite little, barely 1hz.

Image
This is the same mouse but the keyboard is wooting one set to 1k hz. All of a sudden the variance is 20hz. Looks like windows can't even fully handle 1k hz keyboard and mouse at the same time.

With keyboards now supporting 4k hz polling like the Corsair K100, I'm curious how will this affect the stability of 8k hz mouse polling. Seeing that a 1k hz keyboard is enough to destabilize a mouse set to just 1k hz, a 4k hz keyboard would probably trash the stability of a 8k hz mouse.
Solution: Serparate USB controllers and PCI bus lanes per 1 high-pollrate device
MaxTendency wrote:
15 Oct 2020, 20:58
Small update, using the asmedia port for keyboard (the lowest one, right next to the usb-c port) while using top port for mouse seems to minimize if not remove the impact of high keyboard polling on the mouse polls.

Image

Blue is the mouse and red is the keyboard. This combo provided the best polling, pic of polling attached below.

Image
Yeah, that was what I thought. Glad my recommendation helped!

With ultrahigh poll rates, you really need to isolate to one USB chip (and/or separate bus lanes) per high-pollrate device.

PCI-Express USB cards are also another solution that can help this. Plug the keyboard into the motherboard USB, and plug the mouse into the PCI-Express USB. Or do do USB port roulette until you find jackpot. Keep the adjacent ports empty (port above/below a plugged-in high-Hz USB device) because they often share the same USB controller.

This would probably become a staple recommendation of the new 2020s-era "Blur Busters Mouse Guide II"

Until the motherboard manufacturers "keeps up with the Joneses" and have a dedicated-USB-chip keyboard port, and a dedicated-USB-chip mouse port for the 2020-2030s esports era of 4000 Hz keyboard + 8000 Hz mouse + >360 Hz monitors + RTX 3080+ framerates.

This Grand gaming computer upgrade supercycle is going to be very interesting. I rarely see so many concurrent upgrades happen. Those now seem to happen only once every 5-10 years, rather than every 2-3 years in the 1990s-2000s. We are seeing a major Vicious Cycle Effect tick-tock (multiple concurrent frequency upgrades).
Very neat post Chief .

but what about those who have an Intel system with only 1 usb controller ? is the "keep mouse and keyboard as far as possible" rule still applies ? say Ive got a 8khz mouse and 1khz keyboard

HarryDrews
Posts: 11
Joined: 19 Feb 2024, 17:13

Re: TIP: Always put high-Hz keyboard and high-Hz mouse on SEPARATE DEDICATED USB CHIPS.

Post by HarryDrews » 15 Apr 2024, 10:51

b0t wrote:
10 Apr 2024, 13:23
Chief Blur Buster wrote:
16 Oct 2020, 00:29
Houston, we have a problem.

Especially with 4000 Hz keyboards and 8000 Hz mice being used simultaneously.

I just helped someone solve a high-Hz USB performance interference problem between two high-Hz USB devices:

Problem: High-Hz poll performance interference between 1000 Hz keyboard + 1000 Hz mouse
MaxTendency wrote:
12 Oct 2020, 16:35
While I'm pretty convinced that 8k hz mouse polling is going to be not only noticeable but also impactful , I'm starting to wonder how much keyboard polling will affect this. High keyboard polling has known to destabilize the mouse polling and vice versa.

Image
For example this is a 1khz mouse polling on an optimized setup with a 125hz keyboard. As you can see the variance is quite little, barely 1hz.

Image
This is the same mouse but the keyboard is wooting one set to 1k hz. All of a sudden the variance is 20hz. Looks like windows can't even fully handle 1k hz keyboard and mouse at the same time.

With keyboards now supporting 4k hz polling like the Corsair K100, I'm curious how will this affect the stability of 8k hz mouse polling. Seeing that a 1k hz keyboard is enough to destabilize a mouse set to just 1k hz, a 4k hz keyboard would probably trash the stability of a 8k hz mouse.
Solution: Serparate USB controllers and PCI bus lanes per 1 high-pollrate device
MaxTendency wrote:
15 Oct 2020, 20:58
Small update, using the asmedia port for keyboard (the lowest one, right next to the usb-c port) while using top port for mouse seems to minimize if not remove the impact of high keyboard polling on the mouse polls.

Image

Blue is the mouse and red is the keyboard. This combo provided the best polling, pic of polling attached below.

Image
Yeah, that was what I thought. Glad my recommendation helped!

With ultrahigh poll rates, you really need to isolate to one USB chip (and/or separate bus lanes) per high-pollrate device.

PCI-Express USB cards are also another solution that can help this. Plug the keyboard into the motherboard USB, and plug the mouse into the PCI-Express USB. Or do do USB port roulette until you find jackpot. Keep the adjacent ports empty (port above/below a plugged-in high-Hz USB device) because they often share the same USB controller.

This would probably become a staple recommendation of the new 2020s-era "Blur Busters Mouse Guide II"

Until the motherboard manufacturers "keeps up with the Joneses" and have a dedicated-USB-chip keyboard port, and a dedicated-USB-chip mouse port for the 2020-2030s esports era of 4000 Hz keyboard + 8000 Hz mouse + >360 Hz monitors + RTX 3080+ framerates.

This Grand gaming computer upgrade supercycle is going to be very interesting. I rarely see so many concurrent upgrades happen. Those now seem to happen only once every 5-10 years, rather than every 2-3 years in the 1990s-2000s. We are seeing a major Vicious Cycle Effect tick-tock (multiple concurrent frequency upgrades).
Very neat post Chief .

but what about those who have an Intel system with only 1 usb controller ? is the "keep mouse and keyboard as far as possible" rule still applies ? say Ive got a 8khz mouse and 1khz keyboard
There is no technical reason why USB ports of the chipset should have additional delay. In fact, the chipset is connected via PCIe to the CPU. So the likelihood of a random usb pcie card having that bug is no lower/higher than the chipset. Without testing you're just doing blind guessing and there is really no point in changing one unknown to another unknown.

The only intel board I tested, doesn't have this issue... neither did the pcie card

DudeBeFishing
Posts: 11
Joined: 30 Oct 2022, 14:14

Re: TIP: Always put high-Hz keyboard and high-Hz mouse on SEPARATE DEDICATED USB CHIPS.

Post by DudeBeFishing » 18 Apr 2024, 02:13

Has anyone tried one of these adapters? I'm looking for a way to use the M.2 slot connected to the CPU. I don't need it for an NVMe SSD.

The second adapter does not have the controller listed, and it's hidden behind a heatsink. That might be a concern since that means the controller runs hot.

Controller: Renesas uPD720202
M.2 NGFF NVME to USB 3.0 19pin Header Convert Card
https://www.aliexpress.us/item/2251832677662742.html

Controller: ???
M.2 M Key NVME PCIe to USB 3.1 Front Panel Expansion Board Card 10Gb TYPE-E
https://www.aliexpress.us/item/3256804821000367.html

An expensive idea is to get an M.2 to PCIe riser, and put a Startech PEXUSB3S44V. It's a 4 port USB card, with 4 dedicated controllers. It also uses the Renesas µPD720202.
https://www.startech.com/en-us/cards-ad ... exusb3s44v

Post Reply