I have had chronic slow wifi connections on several networks for a while now, I think since my update to 12.04 when it came out. I have tried many of the tips and tricks already available out there in the forums with no luck (wicd, etc..). I want to see if any of you experts out there might be able to help me, and thanks in advance!!

I use ubuntu 12.04 on a lenovo ideapad y650, and most networks I connect to lose the connection frequently or do not give appropriate bandwidth when I am connected.

Here are some results of the usual go-to system checks:

cat /etc/lsb-release; uname -a:

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=12.04
DISTRIB_CODENAME=precise
DISTRIB_DESCRIPTION="Ubuntu 12.04.2 LTS"    
Linux mgeorge-lenovo 3.2.0-48-generic-pae #74-Ubuntu SMP Thu Jun 6 20:05:01 UTC 2013 i686 i686 i386 GNU/Linux

lspci -nnk | grep -iA2 net:

04:00.0 Network controller [0280]: Intel Corporation PRO/Wireless 5100 AGN [Shiloh] 

Network Connection [8086:4237]
    Subsystem: Intel Corporation WiFi Link 5100 AGN [8086:1211]
    Kernel driver in use: iwlwifi
--
08:00.0 Ethernet controller [0200]: Broadcom Corporation NetLink BCM5784M Gigabit Ethernet PCIe [14e4:1698] (rev 10)
    Subsystem: Lenovo Device [17aa:3878]
    Kernel driver in use: tg3

lsusb:

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 007 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 008 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 002: ID 090c:7371 Silicon Motion, Inc. - Taiwan (formerly Feiya Technology Corp.) 

iwconfig:

lo        no wireless extensions.

wlan0     IEEE 802.11abgn  ESSID:"Dyno"  
          Mode:Managed  Frequency:2.412 GHz  Access Point: CC:5D:4E:46:0A:93   
          Bit Rate=150 Mb/s   Tx-Power=15 dBm   
          Retry  long limit:7   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=70/70  Signal level=-40 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:948  Invalid misc:728   Missed beacon:0

eth0      no wireless extensions.

rfkill list all:

0: ideapad_wlan: Wireless LAN

    Soft blocked: no
    Hard blocked: no

1: ideapad_bluetooth: Bluetooth

    Soft blocked: yes
    Hard blocked: no

2: phy0: Wireless LAN

    Soft blocked: no
    Hard blocked: no

lsmod:

Module                  Size  Used by
uvcvideo               67203  0 
videodev               86588  1 uvcvideo
nouveau               712674  3 
ttm                    65344  1 nouveau
drm_kms_helper         45466  1 nouveau
drm                   197641  5 nouveau,ttm,drm_kms_helper
i2c_algo_bit           13199  1 nouveau
mxm_wmi                12893  1 nouveau
wmi                    18744  1 mxm_wmi
joydev                 17393  0 
arc4                   12473  2 
snd_hda_codec_realtek   174313  1 
snd_hda_codec_hdmi     31775  1 
snd_hda_intel          32719  3 
snd_hda_codec         109562  3 snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel
snd_hwdep              13276  1 snd_hda_codec
snd_pcm                80916  3 snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec
snd_seq_midi           13132  0 
snd_rawmidi            25424  1 snd_seq_midi
snd_seq_midi_event     14475  1 snd_seq_midi
psmouse                86520  0 
snd_seq                51592  2 snd_seq_midi,snd_seq_midi_event
serio_raw              13027  0 
snd_timer              28931  2 snd_pcm,snd_seq
snd_seq_device         14172  3 snd_seq_midi,snd_rawmidi,snd_seq
iwlwifi               366509  0 
mac80211              436493  1 iwlwifi
snd                    62218  16 
snd_hda_codec_realtek,snd_hda_codec_hdmi,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,sn
d_rawmidi,snd_seq,snd_timer,snd_seq_device
ideapad_laptop         17890  0 
sparse_keymap          13658  1 ideapad_laptop
cfg80211              178877  2 iwlwifi,mac80211
ir_lirc_codec          12739  0 
lirc_dev               18700  1 ir_lirc_codec
soundcore              14635  1 snd
snd_page_alloc         14108  2 snd_hda_intel,snd_pcm
ir_mce_kbd_decoder     12681  0 
ir_sony_decoder        12462  0 
ir_jvc_decoder         12459  0 
ir_rc6_decoder         12459  0 
ir_rc5_decoder         12459  0 
rc_rc6_mce             12454  0 
ir_nec_decoder         12459  0 
video                  19115  1 nouveau
ene_ir                 18019  0 
rc_core                21263  10 
ir_lirc_codec,ir_mce_kbd_decoder,ir_sony_decoder,ir_jvc_decoder,ir_rc6_decoder,ir_rc5_decoder,rc_rc6_mce,ir_nec_decoder,ene_ir
bnep                   17830  2 
rfcomm                 38139  0 
parport_pc             32114  0 
bluetooth             158479  10 bnep,rfcomm
ppdev                  12849  0 
binfmt_misc            17292  1 
mac_hid                13077  0 
lp                     17455  0 
parport                40930  3 parport_pc,ppdev,lp
tg3                   141414  0 

nm-tool:

NetworkManager Tool

State: connected (global)

- Device: eth0 -----------------------------------------------------------------
  Type:              Wired
  Driver:            tg3
  State:             unavailable
  Default:           no
  HW Address:        00:23:5A:CC:85:BD

  Capabilities:
    Carrier Detect:  yes

  Wired Properties
    Carrier:         off


- Device: wlan0  [Dyno] --------------------------------------------------------
  Type:              802.11 WiFi
  Driver:            iwlwifi
  State:             connected
  Default:           yes
  HW Address:        00:22:FA:D0:94:CA

  Capabilities:
    Speed:           150 Mb/s

  Wireless Properties
    WEP Encryption:  yes
    WPA Encryption:  yes
    WPA2 Encryption: yes

  Wireless Access Points (* = current AP)
    *Dyno:           Infra, CC:5D:4E:46:0A:93, Freq 2412 MHz, Rate 54 Mb/s, Strength 81 WPA2

  IPv4 Settings:
    Address:         10.0.0.43
    Prefix:          24 (255.255.255.0)
    Gateway:         10.0.0.1

    DNS:             10.0.0.1