Solved Windows limiting full fibre?

tmarsh · Nov 3, 2022

I recently upgraded to BT full fibre 900. Since install, speed only reaches 600/650. BT tests from their end show no problems. I dual-boot with Linux mnint and it shows 900+ so I'm thinking it's something to do with my windows setup. I have a Realtek 2.5GBe card add in and have tried a few optimum settings that I found online but speed still down. Any ideas?

Josey Wales · Nov 3, 2022

Are you using a Router?

cereberus · Nov 3, 2022

Josey Wales said:
Are you using a Router?

Virtually all UK setups are combined router/modem based. OP says they get 900 mbs with Linux, so it cannot be router.

I am guessing Windows is just not efficient enough (drivers?) to meet 900 mbs.

Josey Wales · Nov 3, 2022

These are my speeds, I am not on Fiber , my ISP says I am at 1000MB's down which I can get without my router. I don't use Linux at this time but I am also on a Intel Network and am getting close to 900 , it could be the settings on His settings on his realtec card? My wife is using Mint , I will check it on her machine. Her PC does not have a Card that can get that high.

wiganken · Nov 3, 2022

I assume you are using the same test engine in both cases?

I use https://speedtest.btwholesale.com/

clam1952 · Nov 3, 2022

I'd suggest making use of Realtek's diagnostics for the 2.5GBe

https://www.realtek.com/en/componen...0-1000m-gigabit-ethernet-pci-express-software

What happens if you use the motherboards Ethernet?

Josey Wales · Nov 3, 2022

wiganken said:
I assume you are using the same test engine in both cases?

I use https://speedtest.btwholesale.com/

Yes but I use:

Speedtest by Ookla - The Global Broadband Speed Test

Use Speedtest on all your devices with our free desktop and mobile apps.

www.speedtest.net

I also use the MOBO adapter.

torchwood · Nov 3, 2022

as your getting the right speeds on Linux....
compare the driver Version and advanced settings
They should BOTH be using the same driver

SlicEnDicE · Nov 3, 2022

Which browser are you using?

Try the Speedtest client app rather than the browser version.

Also compare results with

Internet Speed Test

How fast is your download speed? In seconds, FAST.com's simple Internet speed test will estimate your ISP speed.

fast.com

tmarsh · Nov 3, 2022

Thanks for all the replies. Yes, I'm using BT's latest hub, and yes I've used the same speedtest. I'll compare the drivers and look at the realtek diagnostic.

tmarsh · Nov 3, 2022

Should have said yes, I've used fast as suggested, alos ookla, thinkbroadband, BT wholesale and they all report 600 odd on windoiws and 900+ on linux.

tmarsh · Nov 3, 2022

clam1952 said:
I'd suggest making use of Realtek's diagnostics for the 2.5GBe

https://www.realtek.com/en/componen...0-1000m-gigabit-ethernet-pci-express-software

What happens if you use the motherboards Ethernet?I ran the diagnostic tool and there is an option to reinstall which changed nothing, the option to repair current setting is not selectable.

clam1952 said:
I'd suggest making use of Realtek's diagnostics for the 2.5GBe

https://www.realtek.com/en/componen...0-1000m-gigabit-ethernet-pci-express-software

What happens if you use the motherboards Ethernet?

I ran the diagnostic tool and there is an option to reinstall which changed nothing, the option to repair current setting is not selectable. The mobo card was giving similar speeds, that's why I added the 2.5.

cereberus · Nov 3, 2022

tmarsh said:
Should have said yes, I've used fast as suggested, alos ookla, thinkbroadband, BT wholesale and they all report 600 odd on windoiws and 900+ on linux

Call BT support?

RFS · Nov 3, 2022

I also have BT full fibre here in the UK. No problem with speed - here's my BT wholesale report. Gigabit ethernet on the motherboard.

SlicEnDicE · Nov 4, 2022

A known fact: Networking on Linux is a lot faster and more efficient than on Windows. Not sure why, but this is how it has always been.

But the difference should not be this huge as OP is showing.

tmarsh · Nov 4, 2022

My speed is consistently around 600, upload is good though!

z3r010 · Nov 4, 2022

I've had some really wild results with that BT speedtest over the years, I don't trust the results one bit.

RFS · Nov 4, 2022

tmarsh said:
My speed is consistently around 600, upload is good though!
View attachment 44194

Your ping is 28ms which is quite slow - mine is 8ms. Wonder if that means anything?

SlicEnDicE · Nov 4, 2022

tmarsh said:
My speed is consistently around 600, upload is good though!

Have you tried clicking here?

hsehestedt · Nov 4, 2022

I'm in the US with gigabit fiber so I can't comment on your service, but the utility you use for testing can make a huge a difference. I know that you tried several.

Here are two tests using different utilities. Note that my system also has a 2.5Gb Ethernet Adapter, although it is an Intel. I have another machine using a Realtek 2.5Gb Ethernet adapter and get similar results.

Note that the results from this first utility sucks wet farts out of dead pigeons:

This next result, taken mere seconds later is much better:

My MUCH older system with the Realtek 2.5Gb adapter benchmarks at 276 / 145 on the first utility and 946 / 940 on the second utility.

Just in case it helps at all, here are my Network Adapter settings for the Realtek card:

ARP Offload: Enabled
Flow Control: Rx & Tx Enabled
Interrupt Moderation: Enabled
IPv4 Checksum Offload: Rx & Tx Enabled
Jumbo Frame: Disabled
Large Send Offload v2 (IPv4): Enabled
Large Send Offload v2 (IPv6): Enabled
Network Address: Not Present
NS Offload: Enabled
Priority and VLAN: Priority & VLAN Enabled
Receive Buffers: 512
Recv Segment Coalescing (IPv4): Disabled
Recv Segment Coalescing (IPv6): Disabled
Shutdown Wake-On-LAN: Enabled
Speed & Duplex: Auto Negotiation
TCP Checksum Offload (IPv4): Rx & Tx Enabled
TCP Checksum Offload (IPv6): Rx & Tx Enabled
VLAN ID: 0
Wake on Magic Packet: Enabled
Wake on pattern match: Enabled
WOL & Shutdown Link Speed: 10 Mbps First