Constantly need to "reset wireless network adapter"

Setup:

Ethernet from modem to router then:

Ethernet from router to Desktop

Ethernet from router to Ooma (Phone)

Ethernet from router to Sonos Controller

About 1/2 a year ago, I would typically lose my wireless internet connection once or twice every hour I was using my laptop.  I kept having to "Reset Wireless Adapter".  A housemate using a different Dell laptop (don't know which model) did not have any problems with dropouts.  I lived with the issue b/c I mainly use my desktop.  Now, my desktop is having the same problem. 

How do I fix this "problem"?  I work from home and I can't have my connection dropping out all of the time. 

TIA!

System Info:

Dell Desktop Studio XPS 8100 running Windows 7 Home Premium Service Pack 1

Network Card: Broadcom Netlink Gigabit Ethernet PCI express x1 (OEM)

Network Card: Qualcomm Atheros DW1525 (802.11N) WLAN PCIe (OEM)

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Dell Laptop XPS 1647 running Windows 7 Home Premium Service Pack 1

Network Card:  Intel Centrino WiMax 6250

Network Card: Intel Centrino Advanced-N 6250 AGN

Network Card: Broadcom Netlink Gigabit Ethernet PCI express x1

Network Card: Dell Wireless 370 Bluetooth Mini-card (never use Bluetooth)

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Router: Netgear WNDR 3700 (have had for 3 - 4 years)

Modem: Motorola Surfboard SB6141

ISP: Time Warner