Okay so it's not normal for me to post for help here, but I will give it a try anyways, since this is a complex problem.
Ok when you first read this it appears as it may be a problem on a network level. However once we dig further in, it appears as it's not a network problem. See bottom for equipment used.
Okay the problem was my onboard Marvel Gigabit LAN was creating incorrect checksum's in TCP packets. Here is a screenshot of what is happening http://img523.imageshack.us/my.php?i...dmarvel3lk.jpg
I also had issues of randomly dropping connections. My first idea was a network problem, so I test the network equipment. Cable is OK, switch is OK. I use both high end cisco switches and SMC switches to test this problem, and it occurs on both.
I temporarly replace the NIC with a Realtek RTL 1839 based D-Link network adapter, and most of the problems dissipear. I did not do thorough testing with this card, and some errors could have been still happening I was not aware of.
So I replace my onboard NIC with an Intel Pro/1000 GT which is a 50$ high end network card. Now this is a full featured card as well, so some diagnostics come in handy. The problems still occur with this card in, but I make some other discovery's with this in.
Before we go on, I would like to give a brief history of has recently happened to this computer. A few months ago I had a soundblaster Live 5.1 which fried in this computer. Card had an echo, than suddenly fried bad enough the PC would not boot with it in . These cards are crap, but are terribly reliable and tanks. A few days ago, the PC refuses to boot, it will not even start the POST sequence. I reset CMOS and reassamble the PC. I dismiss the problem as a lack of PWR_GOOD signal due to possible short circut's caused by some cables (which were replaced) or dust collected on PC parts.
Okay enough with the history. The new network card supports the PXE (Pre-boot execution enviroment, used aqquiring DHCP info and booting diskless PC's). Now when I loose network connectivity I rebooted the PC. Upon booting, the PXE cannot aqquire an IP address (DHCP info). This rules out the operating system and drivers as the problem, as the network card before windows boots cannot talk to the network. I also ran all the diagnostics on the card (In windows) while I was listening to some music. They come back ok. However during the diagnostics, my audio skips. I am using a professional PCI soundcard so the soundcard was not the problem. This makes me think about this being an issue with the chipset or PCI Bus. Also, when I loose network connectivity I can still ping the local TCP/IP stack (127.0.0.1)
My network, network card, cables, power supply are all ok. I am starting to think this maybee a motherboard issue.
*****Things still yet to try*****
-Enable PNP OS in Bios, however this will unlikely help, as I encounter problems out of the OS.
-Swap the card to more PCI slots.
*****Hardware Used***** (None of it is overclocked)
Thermaltake TT-420AD (Power fully in spec)
Asus A8V Deluxe (Via K8T800 Pro and VT8237)
2x 512 meg PC3200 Ram (Memory tests fine)
M-Audio Audiophile 2496
AMD 3400+ Socket 939 (Same as 3500+)
Intel Pro 1000/GT Network Adapter