Advice Needed RE: Langley Platform

[senthumax]

Hi Steph and friends,

Finally Installation Engineer came yesterday and fixed my outside cable issue.
But still i am not getting 20Mb all the time. my downstream is not stable.

Last night i spoke with one of the VM technical staff over their hotline
he was saying i am in Langley platform my SNR and Signal Level are Pretty much high for my platform. i don't understand totally what he was talking to me.

Also he was saying i should get get 28-33 on SNR and power level Should be negative reading.

At the moment i am getting:

Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 5
Downstream Frequency : 331000000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 6.1 dBmV
Downstream SNR : 41.4 dB

Upstream Lock : Locked
Upstream Channel ID : 3
Upstream Frequency : 25800000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 46.5 dBmV
Upstream Mini-Slot Size : 2

My question is:

Is there any possibility that the High SNR and High Power level effect my Download speed?

to be honest in early morning 1am to 6am i tested my download speed via rapid share i a getting 1.8Megabyte to 2.4Megabyte (i use Internet Download Manager)
but in other times i am getting 1.5Megabyte to 1.6Megabyte
from 6pm to 11.30pm iam getting 700KB to 1.3Megabyte

Finally arranged a senior service engineer for this friday regarding my Unstable connection.

Note :i was getting spot on 20Mb since last year. but this new probs only started from the begining of jan 2010.

[Sephiroth]

Personally I'd fit a 3dB forward path filter to the back of my modem to bring the received power down. The SNR would fall too although, IMO, you can't get an SNR that's too high provided that the receive power isn't too high.

Those are the same figures, by the way, that you had when the outside wall was a mess.

Others have advised not to test your speed on Rapidshare but rather on the VM download site http://www.virginmedia.com/testmyspeed/manual.php. Please do this and report.

[Ignitionnet]

The VM guy has no idea what he's talking about, all of those levels of yours are just fine.

There is no guarantee of getting maximum speeds all the time and certainly not from that festering pit of child porn and warez that is Rapidshare.

Bad signals will affect you all the time and not stop affecting you during periods of low load on the network.

You could use an attenuator if you really want to, would probably not drop the SNR as it would attenuate both signal and noise equally, but it would be a pointless exercise.

The differences between platform are due to legacy analogue signals. Given a lot of areas have had analogue switched off one size fitting all is an appropriate assumption now.

As advised try testing your speed using something more reliable than Rapidwarez and if the timing differences you mention still apply it's network congestion, and as a reminder you are paying for an 'up to' service with no guarantee of 24x7 performance.