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[reportXubuntu <802902@xxxxxxxxxxxxxxxxxx>]

At last found where the two beasts are.
one is little one and  other is a big one :D 

The little beast - device was to hot.

I have disassemble plastic cover, and was using usb adapter 
without plastic cover. When i decided to change usb port and to use usb cable (1,5 m in length ), 
i find out that chip   (rtl8187b; 74307S1; G716D TAIWAN)
is quite hot (betwen53C and 60C).

The big beast - device was directly connected to laptop usb port
(and maybe pick up some nice interference from build in intel wireless card or from another electric circuit ).

I tested few positions with usb cable and find out that it really matter adapter orientation,
and  how far away  adapter is from laptop (in my situation about 70cm was enough to get good results ).
 
Test results:

without cooling (chip rtl8187b up to ~59C) 
and with usb cable about 70cm from laptop, adapter is hanging down with led pointing to router.

--- 10.0.0.138 ping statistics ---
208 packets transmitted, 127 received, 38% packet loss, time 207181ms
rtt min/avg/max/mdev = 0.806/3.346/148.845/13.007 ms

with cooling (chip temperature up to 34C) 
and other things are all the same

starting cooling:
--- 10.0.0.138 ping statistics ---
204 packets transmitted, 181 received, 11% packet loss, time 203239ms
rtt min/avg/max/mdev = 0.752/3.685/174.709/17.437 ms

hand get tired and i put ventilator on the table

--- 10.0.0.138 ping statistics ---
111 packets transmitted, 110 received, 0% packet loss, time 110108ms
rtt min/avg/max/mdev = 0.695/5.633/228.638/26.297 ms

while downloading gimp windows install (86,0 MB) and still cooling

--- 10.0.0.138 ping statistics ---
194 packets transmitted, 193 received, 0% packet loss, time 193214ms
rtt min/avg/max/mdev = 0.727/14.372/749.374/72.800 ms


still cooling :D
--- 10.0.0.138 ping statistics ---
225 packets transmitted, 225 received, 0% packet loss, time 224268ms
rtt min/avg/max/mdev = 0.721/3.329/193.260/17.353 ms



So i am not an expert on electric circuit, neither on usb wireless adapters electronics,
but it is really something to do with drivers and maybe power management or 
power consumption for some routines.
Maybe windows drivers use smarter algorithms to do the same job than linux drivers,
and that's why chip in linux has more job, use more power and gets over hot and starts malfunction?
Or maybe it is usb power management? 
But to answer exactly man need to have knowledge and understanding about this device (chipset), or 
in another words need team assistance which crated this device (chipset).


So problem solution is to put cooler and use usb cable :D

But still annoying why in windows it works ok even when adapter is hot
and on linux need to be cooled down to 30C ?

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https://bugs.launchpad.net/bugs/802902

Title:
  Realtek rtl8187b wireless chipset slow speed

Status in The Linux Kernel:
  Invalid
Status in “linux” package in Ubuntu:
  Fix Released

Bug description:
  Hi, I have ubuntu 11.04, all updates, wifi chipset rtl8187B, kernel 2.6.38-10, and 14mbit/s internet connection. 
  When I try to download something, for example from torrents, I see ping up (up to 500-800ms), slow speed (<1mbit/s) and packets lost.
  In windows its works fine, ping didnt up, download speed 14mbit/s. 
  So if I want to download something, I need to reboot from ubuntu to windows, or wait for download at low speed in ubuntu. And it's not good=(
  Thanks, and sorry my bad english.

  laptop:~$ uname -a
  Linux mike-laptop 2.6.38-10-generic #44-Ubuntu SMP Thu Jun 2 21:32:22 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

  laptop:~$ modprobe --show-depends rtl8187
  insmod /lib/modules/2.6.38-10-generic/updates/drivers/misc/eeprom/eeprom_93cx6.ko
  insmod /lib/modules/2.6.38-10-generic/updates/net/wireless/cfg80211.ko
  insmod /lib/modules/2.6.38-10-generic/updates/net/mac80211/mac80211.ko
  insmod /lib/modules/2.6.38-10-generic/updates/drivers/net/wireless/rtl818x/rtl8187/rtl8187.ko

  laptop:~$ sudo lsusb -d 0bda:8187
  Bus 001 Device 004: ID 0bda:8187 Realtek Semiconductor Corp. RTL8187 Wireless Adapter

  ProblemType: Bug
  DistroRelease: Ubuntu 11.04
  Package: linux-image-2.6.38-10-generic 2.6.38-10.44
  ProcVersionSignature: Ubuntu 2.6.38-10.44-generic 2.6.38.7
  Uname: Linux 2.6.38-10-generic x86_64
  NonfreeKernelModules: nvidia
  AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
  Architecture: amd64
  ArecordDevices:
   **** List of CAPTURE Hardware Devices ****
   card 0: Intel [HDA Intel], device 0: ALC269 Analog [ALC269 Analog]
     Subdevices: 1/1
     Subdevice #0: subdevice #0
  AudioDevicesInUse:
   USER        PID ACCESS COMMAND
   /dev/snd/controlC0:  mike       2412 F.... pulseaudio
  Card0.Amixer.info:
   Card hw:0 'Intel'/'HDA Intel at 0xfcb00000 irq 43'
     Mixer name	: 'Realtek ALC269'
     Components	: 'HDA:10ec0269,144dc06a,00100004'
     Controls      : 13
     Simple ctrls  : 8
  Card1.Amixer.info:
   Card hw:1 'NVidia'/'HDA NVidia at 0xddefc000 irq 16'
     Mixer name	: 'Nvidia GPU 0b HDMI/DP'
     Components	: 'HDA:10de000b,10de0101,00100100'
     Controls      : 16
     Simple ctrls  : 4
  Date: Tue Jun 28 13:24:48 2011
  HibernationDevice: RESUME=UUID=339679fe-6015-48a0-b9f5-9bdecde05562
  InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Beta amd64 (20110405)
  MachineType: SAMSUNG ELECTRONICS CO., LTD. R530/R730/P530
  ProcEnviron:
   LANGUAGE=ru_RU:en
   PATH=(custom, no user)
   LANG=ru_RU.UTF-8
   SHELL=/bin/bash
  ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.38-10-generic root=UUID=eae27d1a-6cca-45bb-8c38-d8cdd238b079 ro quiet splash nomodeset video=uvesafb:mode_option=1377x768-24,mtrr=3,scroll=ywrap vt.handoff=7
  RelatedPackageVersions:
   linux-restricted-modules-2.6.38-10-generic N/A
   linux-backports-modules-2.6.38-10-generic  N/A
   linux-firmware                             1.52.1
  SourcePackage: linux
  UpgradeStatus: Upgraded to natty on 2011-05-04 (54 days ago)
  dmi.bios.date: 06/21/2010
  dmi.bios.vendor: Phoenix Technologies Ltd.
  dmi.bios.version: 04KQ.M007.20100621.KSJ
  dmi.board.asset.tag: Tag 12345
  dmi.board.name: R530/R730/P530
  dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD.
  dmi.board.version: Not Applicable
  dmi.chassis.asset.tag: No Asset Tag
  dmi.chassis.type: 9
  dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD.
  dmi.chassis.version: N/A
  dmi.modalias: dmi:bvnPhoenixTechnologiesLtd.:bvr04KQ.M007.20100621.KSJ:bd06/21/2010:svnSAMSUNGELECTRONICSCO.,LTD.:pnR530/R730/P530:pvrNotApplicable:rvnSAMSUNGELECTRONICSCO.,LTD.:rnR530/R730/P530:rvrNotApplicable:cvnSAMSUNGELECTRONICSCO.,LTD.:ct9:cvrN/A:
  dmi.product.name: R530/R730/P530
  dmi.product.version: Not Applicable
  dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD.

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