Weird Windows 7 Home Network issue.

Hi
This one is strange.
I have had a Xp based network for years with no problems. Remote desktop connection to a shared computer. The same shared computer would have various drives that were shared and I could map network drives from it or remote desktop to it without issues.
I recently upgraded my office laptop to a newer computer and it is running windows 7 Pro.
Upgraded the shared computer( named Grunt) with shared drives to windows 7 at the same time.
Ever since changing my computers to Windows 7 I have a problem that has been reoccurring.
The Grunt will disappear from the network, the mapped drives will stop working(in the middle of streaming or copying a file) or/and the remote desktop connection will disconnect.
Very frustrating.
Won't reconnect unless grunt is rebooted and it doesn't stay connected long.
Have tried many things with various results. Thought I had the fix many times, but I don't.
Replaced cable. Disconnected from managed switch and plugged directly to wireless router. Both computers running Win 7 are connected directly to router..
All computers same workgroup.
Windows 7 computers same homegroup
Looked online and saw that other people have had similar issues for years.
Unchecked ipv6 in adapter properties ...on all Win 7 Machines
Some fixes on the internet said to edit the registry
HKLM\system\CurrentControlSet\S....etc
Problem is I have no HKLM section in MY registry...
What can I do to fix this problem?
I just noticed that if I connect from my laptop wirelessly and disable the ethernet adapter it seems to stay connected longer...still operating wirelessly but the transfer speeds of files is 3 megs per sec instead of 60+
Also when Grunt disappears one shared resource remains..on Grunt...It is a folder that contains an old backup for my xp laptop that I replaced with the current Win 7 Laptop....???
Could this be a result of improperly sharing the drives?
ie Should I disable the drives that are shared and start over differently.
I really am in a bind here
Joe
I don't want to have to change grunt back to xp....

So one of the sites suggested that I shut off flow control.
Apparently the Atheros L1 Gig onboard controller on my P5B sucks and I disabled flow control.
Texted a buddy and we bonded over what could be the problem. He put me on the right path.
I was trying to update the driver and got bored waiting for Windows to find an update on the web. It was lookin and lookin so I decided to give it time and after watching a porn and a half I decided to surf google.
Turns out the onboard nic has issues and it could be better to install a pci NIC.
Right...
Changed the properties settings on flow control and....
Turned the computer off....cold.... with a reach around to the power supply.

Works like a charm now
Later Dudes