Vista networking and graphical problems

[Genocidicbunny]

So, I recently got a new pc and considering that it has 4GB RAM + 896mb video card, I installed Vista Ultimate x64. Now I'm having several problems related to networking and graphics.

First, the networking issue:
Whenever the pc comes back from sleep mode, I cannot access the internet. A reboot fixes this, but completely defeats the point of sleep mode. I've tried unchecking the "Allow Windows to turn off this device to save power" option and with it off, Windows reports that im connected to the network after sleep mode. No internet connection though.

The graphical issue ( may be related to other things too actually ):
Sometimes, when I play a game the computer will stutter for 10 seconds or so and then resume the game. Once in a while, Windows will say that the graphics driver has encountered an error and recovered, but this causes the game to CTD. Other times, especially in Company of Heroes, the game will resume, but the frame rate will halve. Every time this stuttering occurs it will halve again, so my 60fps quickly becomes 30 then 15 then an unplayable 7.5. Company of Heroes itself shows no warnings in warnings.log.
I've checked, and at the height of the game, the GPU doesnt get above 50C. Processor is being utilized 15% or so as well. Temperatures are all fine, so I doubt its a heat problem.

The networking issue seems to be somewhat common, at least according to my googling, but none of the offered solutions worked.

As for the graphical issues, one idea I have is that my overclock isnt stable, but if so, why did it pass a 24 hour Prime95 torture test?

The specification:
Intel Core 2 Quad Q9550 @ 3.4ghz
EVGA 780i SLi motherboard, BIOS v6.00PG ( according to dxdiag - can probably be upgraded, but I see no real reason)
EVGA GTX 260 Core 216 OC edition - ForceWare 180.84
4GB Corsair 1066mhz RAM - passes Memtest86
Windows Vista Ultimate x64 SP1 - updated completely as of Dec 24th.

Edit - I changed my voltages and cpu speeds back to stock and the problems still continue. Im going to try to install XP to see if it is a Vista-related issue or not.

EDIT 2: I just solved half the problem ( the graphical bit) by uninstalling Forceware 180.84 and installing the previous version ( 178.something) Got through a hour long game of Company of Heroes with no stuttering. Did notice a drop of a few fps, but compared to halving every 15 minutes, its nothing.

I would still love some suggestions for the sleep mode networking issue though.

 

[Cutlass]

You might want to check the Windows updates and see if anything is new from your install. After that, check that your drivers are as up to date as possible. Especially video, main board, and communications drivers. Then, how are you accessing the net? Sometimes if the PC has been idle, the modem might be in a sleep mode and need to be reset.

 

[Genocidicbunny]

All drivers are as updated as they can be right now. Windows updates are complete as of today.
I access the net through an ethernet cable connected to the router which is then connected to the modem so I don;'t think the modem falling asleep is the problem.

 

[Genocidicbunny]

EDIT - Whoah, that was one delayed double-post.

 

[Cutlass]

With what you've said so far I have no further ideas. I simply do not use sleep mode on a Windows PC. Despite the fact that Windows makes sleep default over shut down, Windows simply isn't good enough to run without periodic reboots. So I feel there's nothing gained. I'd delete the option altogether if it wasn't a pain in the ass to do.

 

[GenMarshall]

Strange, never encountered any problems when I place my desktop to sleep. Then again, I only put my desktop to sleep when I am going to be away to eat or do laundry. More oftenly, I shut down my desktop if I am going to be not using the computer for more than an hour.