Low speed ADSL link

I'm a bit clueless about the ADSL technology.

I've recently upgraded to ADSL max with Enta (ukfsn), but cannot get anything faster than 3500Kbps download speed according to speedtester.bt.com. As part of the move, I replaced my old Alcatel Speedtouch 510 with a Zoom X6. So I'm wondering if I've possibly got a dud router or if I should have done something to the wiring, other than just plug in the new router.

Enta says that BT can find nothing wrong and are offering to come and look at the problem to see if it's something to do with my network for a very reasonable 160 quid + vat (!*!), shoud it turn out to be my end that's at fault. Apparently, I get nothing if it's their fault.

When originally installed (by BT with a very old BT router), I got a single filter on the main point where the BT wires come into the house, so I don't have any microfilters.

Here's my router's stats:
ADSL Line State: Showtime
Downstream: 8128 Kbps
Upstream: 448 Kbps
Mode: ADSL2PlusAuto
Transmit Power: 11.9 dB
ADSL Link UP Time: 21 day 5 hour 19 min 51 sec
Operational Mode: G.Dmt

Item Downstream Upstream
SNR Margin 15.5 dB 24 dB
Line Attenuation 16.0 dB 11.0 dB
CRC Errors 930 2
FEC Errors 0 0
HEC Errors 497 0

Any thoughts or pointers? or do I just take that horrid one way bet with BT?

Tim
ps does anyone know how to coerce the X6 to change its MTU - it only comes with documentation for the nasty (and rather flakey) GUI

What does the BT speedtester say your IP profile is?
Do any of the congestion checkers suggest that your exchange might be suffering virtual path congestion?
Are you out of your 10 day training period?

If those are your normal stats there is nothing wrong with the link between you and the exchange. Certainly nothing for BT to fix. You are syncing at the maximum normal ADSL rates (8128/448).

Perhaps you need to tweak your Window's settings.

Try the freeware TCPOptimizer.

http://www.speedguide.net/downloads.php

Actually for that attenuation and noise margin there are a shedload of CRC errors.... My own attenuation is 23dB and in 31 days I clocked up 54 CRC errors in total...

For 21 days that is nothing. Those errors could have all happened with a noise burst a few milliseconds long.

OP: reboot your router, I didn't realize it had been on so long. Leave it off for at least 1/2 an hour and then switch it back on. It may kick BT's systems into sorting your profile out.

Check your current profile here: http://www.speedtester.bt.com/

just now
"Test1 comprises of Best Effort Test: -provides background information.
IP profile for your line is - 7150 kbps
DSL connection rate: 448 kbps(UP-STREAM) 8128 kbps(DOWN-STREAM)
Actual IP throughput achieved during the test was - 2693 kbps

If you wish to discuss these results please contact your ISP."

Hmm. I do have a couple of windows boxes, but I'm getting this throughput on linux, too. I get the same results (within the variance that I get for different times of day) for wired and wireless connections, Linux, and Windows.

Can I really get that speed up by a lot by futzing with the IP protocol? If I can, I'd expect that the router's the most likely bottleneck and there doesn't seem to be much to alter there.

I don't think that there's much wrong with my LAN set ups, not that could cause such a large drop off in rate.

As per other thread, I'll power down the router and see what that does

That is a few CRC errors, but not so many that I think it's causing the performance hit - although they could be a symptom of the same underlying issue, I suppose.

Otherwise, the stats look ok, do they? And if they do, can I assume that it's nothing to do with the BT side of my router?

Entanet can slow down to those levels at weekends and off-peak hours check your connection with the following link
http://adsl24.co.uk/centralstatus.php

this will tell you which central you are connected to at entanet and what the expected maximum download speed you can expect when the ALT (anti loss tool) is in opperation, speeds can be reduced to as low as 2Mbps generally 10pm-2am weekdays and 10 am -12pm weekends.
If your speeds are much bellow these values then you do seem to have a problem.

the UKFSN rep posts regularly on the EntaNet forum if you need more help.

They are the best stats possible for normal ADSL (business ADSL can increase the upstream to 832 kbps). You have the maximum profile 7150 kbps.

You should be regularly getting >6000 kbps downloads with that profile (and sync rates). Have you restarted your router?