Network gurus – help w. high CPU utilization – 1Gb/s network – BTVLink stutters

[mapleleaf]

I have been experiencing terrible issues with BTV lately. Whenever I record anything on my BTV server, CPU utilization will skyrocket to about 80 % despite the fact that all my TV tuners have hardware MPEG2 encoding... Showsqeeze and Smartskip are disabled. Then when I try to play anything trough BTVLink, all I get is horrible stutter and my BTVLink becomes essentially unusable. Basically only time I can use BTVLink is when BTV server is completely idle. I have already completely reinstalled WinXP, my system is in pristine condition, however, high CPU utilization remains… It seems that with every BTV version it needs more and more resources. I’ve pretty much given up trying to make BTV to behave…

Other thing I have noticed is that my 1Gb/s onboard NIC taxes my CPU tremendously as well. My MOBO is ASUS P5P800 with built-in 1 Gb/s Marvell NIC. When I try to access files on my BTV server while it is recording, NIC itself will use close to 90% of CPU. Together with BTV using so many resources I am pretty sure that this is what brings my BTV server to its knees. When BTV is not active on my server, I get excellent transfer speeds, but the moment it will start to record something my network performance (BTV sever only) becomes 100 times (literally) worse.
Any idea why my home 1 Gb/s network would utilizes my CPU so much? (my 1Gb/s 16-port switch supports jumbo packets but enabling it or disabling it on my NIC makes no difference). I have no PCI slot left so I could install add-on NIC (they seem to use CPU a lot less).