Slow network access on new computer

I bought new hardware yesterday and now DO is slow on network access, also when moving files within the same networkdevice via d'n'd. Copying is okay, it's just a delay in the lister (1-2 sec.) Accessing TO the pc from another with DO runs fine. Under WExplorer there's no delay.

I found out when WMP11 is running there's no delay in DO's lister!!! I installed Vista Ultimate 32-Bit twice, same effect.

Maybe it has got to do with the new hardware (P35 chipset and Core-2-Quad CPU)?

Additional info: I found out, that if the network is busy (for example Internet downloading or copying something via network), DO gets "normal" network speed.

Sounds quite strange. Is it a Wifi network? Some of the Vista drivers for Wifi cards are pretty awful at he moment and I had some strange (but different) problem with certain drivers/versions.

Solved it: It was the LAN-driver (Attansic L1 1GBit), just installed an older one and now it works fine again.

Asus should use the Realtek chips again!