Is my DSL capable of speeds >40mb/s

My router informs me…
Downstream line rate (kbit/s): 39997 (I regularly achieve speeds greater than 35mb/s)
and…
Maximum downstream rate (kbit/s): 65848

I asked in my ISP's forum about upgrading to Fiber 65, but was told by an mvp that my line wasn't capable, regardless of what the max downstream rate indicates.

Should I take that as granted?

Your answer is in what you have given above. YES your line will support 65Mbps - or possibly more if SNR trains down to 3dB.

The information from your ISP forum is basically "rubbish".

Thanks for the reply.

Other figures indicated by my router, if they make any difference…

Upstream noise safety coefficient (dB): 10.4
Downstream noise safety coefficient (dB): 8.8
Line standard: Vdsl2_ANNEX_B
Upstream line attenuation (dB): 4.1
Downstream line attenuation (dB): 11.9
Upstream output power (dBm): 7.0
Downstream output power (dBm): 14.0

It depends.

If it's an ECI cabinet and interleaving is enabled the max attainable rate is exaggerated by about 10%.
In that case it would be around 58Mb/s

If it's a Huawei cabinet with G.INP then the line could actually achieve higher. The max attainable quoted is based on the current target SNRM which will be 6dB at the moment.
Huawei cabinets can go as low as 3dB target SNRM which would see the line reach between 74-76Mb/s if the DLM lowered the target to 3dB.

If it's an Asus modem with a Mediatek chipset then the max attainable figure is plucked out of thin air and is usually massively exaggerated.

So if it isn't an Asus modem the line could achieve anywhere between 58Mb/s and 76Mb/s, depending on whether it's an ECI or Huawei cabinet you are connected to.
There are ways to check which cabinet you are connected to.

Enter your address in to the BT Wholesale Broadband Checker and post the cabinet number and exchange quoted on the top line and I'll have a look.

https://www.broadbandchecker.btwholesale.com/#/ADSL/...

There are two green cabinets at the end of my block, neither have any identification at all – all I know is the exchange.

Here's a screenshot of the information displayed after entering my address into the form provided by the broadbandchecker link.

broadbandchecker

It's a Huawei cabinet so you are looking at the figures I quoted above for the Huawei (between 65 - 76Mb)

I have no idea why your provider is telling you it isn't worth upgrading.
The VDSL range estimates on the broadband checker you just screen shot are the estimates the provider sees.

It looks well worth the upgrade to me if you need the extra speed.

Edited by j0hn83 (Fri 28-Jan-22 12:35:16)