Low Speedtest Results

[#1]

My IP Rate and the PlusNet equivalent is 3000kbps but speed tests and http download tests (including the BT Speedtester) only give speeds of about 1800kbps.
Any suggestions as to the problem. Note that the IP Rate until about 2 days ago was 2000kbps
Edit - this is a PlusNet problem. I just changed to the RIN connection  and speeds are now 2900kbps
Is this a function of now being on BBYW2 or is there a problem with the network

[#2]

Apologies for the bump but this one seems to have been missed.
I would really like a rep to have a look at it.

[#3]

Hi Jim,
I can't see anything that's obviously causing your problem - your line is profiled at 3000Kbps at both our end and BTs.
I'd appreciate it if you could try tweaking your MTU and rWin settings for a 3000Kbps connection and then try running a BT Speedtest after rebooting your computer and router.

[#4]

I am on Vista 64 bit - and it has always worked OK when I was on PAYG  - no difference between RIN and PlusNet.
Now on BBYW2 there is a significant difference on BT speedtest, PlusNet speedtest and http file download from the Kaspersky software download.
I can't fiddle with Rwin in Vista and MTU isn't a good idea either unlike XP

[#5]

Update - switched back to PlusNet servers and speeds are just under 3000kbps.
The only thing I can suggest is that the jump from 2000 to 3000 didn't happen until I disconnected and reconnected to the PlusNet servers - anyway it seems to be fixed 

[#6]

When the Plusnet profile increases I've noticed it is sometimes necessary to disconnect from Plusnet and reconnect to benefit from the increased value.
Perhaps the same is true when it goes down but in that case the BTw RAS applies the rate limit so the effect wouldn't be noticeable.

[#7]

According to Plusnet my profile is 7000KBps
My Sync rate is 7968 Kbps
The speedtester gives :-




etc...
BTW My exchange contends that there is no contention.

[#8]

Axis - out of interest what does the BT speedtester give you?
If it's markedly higher, tweak your MTU and RWIN.
B.

[#9]

The BT speedtester gives me a java error
But - before it crashed it confirmed that Plusnet's value of 7000Kbps is correct.
Since I am using Linux, it will choose optimal values for RWIN/MTU
Investigation shows that MTU is 1500 (which is the same as my router)
/proc/sys/net/core/rmem_default = 122880
/proc/sys/net/core/wmem_max = 16777216
My send window values are the same as the receive window sizes.