Would my low SNR cause slow speeds?

I'm on Eclipse's Evolution 4 package, and live only a few hundred metres from my exchange, Synch at 8128 / 448 constantly, but although I never have any disconnections, I have had really poor speeds for months. These are the line stats from my router:-

ADSL Link-------------Downstream-------Upstream
Connection Speed------8128 kbps--------448 kbps
Line Attenuation---------14.0 db------------5.5 db
Noise Margin-------------7.7 db-------------25.0 db

Although my line attenuation is quite low (which I believe is good), my noise margin is also low, which I believe is bad. Any suggestions as to what the problem could be? I complete my migration to Aquiss on Wednesday, and I'm hoping that my low noise margin isn't going to be a major problem?

Any advice is appreciated, cheers.

If you don't get any disconnections, then thats fine.

And having a low SNR would not give you poor speeds at all.

Mines 8128 kbps @ 6-6.5db and I can acheive 6.5 meg at off peak times. More likely ISP pipe congestion (reading the Eclipse forum) or local exchange contention. My bets are on ISP reasons.

Just what I wanted to hear, thanks.

In reply to:

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And having a low SNR would not give you poor speeds at all.

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Traffic will pass through your connection at the same speed regardless of the noise. However, if the SNR is too low, your receiving system will not be able to make sense of it and ask for packets to be repeated. Two or three times as much data will pass through at the expected speed, but you will only see it arriving in a useful form at a considerably lower rate. Is that not going to mean a poor speed?