It's related more to your hardware than your OS. Improvements can be made by changing some configuration settings, but it's more trial and error to find the best settings.
My newer HP laptop (Win7 upgrade to Win8.1) sits five feet away from my ancient HP desktop (originally Win98 upgraded to XP)
The laptop has an internal 801.11 N adapter and the desktop uses a 802.11 G USB adapter.
I have fiddled with the laptop settings ad infinitum and rarely get more that 36 Mbps, it usually hovers around 19 Mbps
The desktop how ever screams at full 56 Mbps without any adjustment.
That takes into consideration the same radio noise for both machines and devices, they connect to the same router.
Bottom line - the network adaptor in the laptop is terrible. Worse, HP had locked the HW to only a few choices.
Read the manual for your device and see if they offer any advice on improving throughput.
That's all I have at the moment, good luck.
Bill
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