experiencing slow internet connection with non-free-firmware

[Abhishek Dixit]

Hi,
to be able to use wireless on my laptop (Natty 64 bit) I had to
install linux-firmware-nonfree for the device to work.
How ever I have noticed the device (or my internet) is slow when I am
using Ubuntu.At the time of writing this email I have only 4 firefox
tabs open with no video streaming site.
Simple blogs and Gmail.Which took an unusually long time to load.
If I do the same (which I did in my dual boot) the connectivity is quite fast.
I am the only person using this internet so there is no problem of
network overload.
I use an ADSL broadband and solely the single user for it.
I have booted Windows 7 and Natty both and I found that my internet is
working better (faster) in Windows 7 than Ubuntu 11.04.
I do not know what statistics to report in support of this argument
(in case any one interested to dig it let me know what details to
provide).
I suspect some kind of firmware upgrade or update is needed can some
one point what did I do wrong?
My device wifi

0c:00.0 Network controller [0280]: Broadcom Corporation BCM4312
802.11b/g LP-PHY [14e4:4315] (rev 01)
        Subsystem: Dell Wireless 1397 WLAN Mini-Card [1028:000c]
        Flags: bus master, fast devsel, latency 0, IRQ 17
        Memory at f69fc000 (64-bit, non-prefetchable) [size=16K]
        Capabilities: [40] Power Management version 3
        Capabilities: [58] Vendor Specific Information: Len=78 <?>
        Capabilities: [e8] MSI: Enable- Count=1/1 Maskable- 64bit+
        Capabilities: [d0] Express Endpoint, MSI 00
        Capabilities: [100] Advanced Error Reporting
        Capabilities: [13c] Virtual Channel
        Capabilities: [16c] Power Budgeting <?>
        Kernel driver in use: wl
        Kernel modules: wl, ssb


-- 
Regards
Abhi