NVidia 780i system freezes

I cant be sure its the mainboard or the vid card, so I will just post this here for now.

I have the nVidia 780i XFX board, p4 3.0 8400, 4gb ddr2 800 ram, winXP pro sp2, 2 xfx nvidia geforce 8800gt vid cards, and a gateway 24" monitor 1680×1050

since i got this board, I have run into an odd issue. while everything else works beautifully, the system freezes whenever I watch a movie file (AVI, MPG, etc). It freezes at random regardless of the decoder in use or any background applications (if any). So far, it has ONLY frozen when viewing movie files.

when the system freezes, it typically just locks the audio in a loop and the screen stops as usual. however, SOMETIMES it will preview the crash. the video playback will start showing many vertical lines like someone is running a blender in the other room and then the video freezes...sometimes the audio will keep going but the video freezes until I hit the reset button. In some cases, when I see the vertical lines appear, I try to close the media player before it can crash. This does not work, but sometimes the video gets all crazy, the colors change, the resolution goes incredibly low, the refresh speed slows to a crawl like when a window leaves a trail on top of a non-responsive window.

I have the latest geforce drivers as well as the mainboard downloads.
I tried changing the video card from the e-GeForce 8800gt to the XFX 8800gt.
I tried running one vid card, two, and two in SLI mode, no change.
I tried changing the memory from patriot to corsair, same speed and capacity.
I tried using 2gb of ram, and changing between single and dual channel
I made sure it wasnt a codec problem, it freezes for multiple codecs
It does not appear to be heat related, the nVidia monitor logs show the GPUs never went above 142F and the CPU never went above 105F, I am running an inflow/outflow fan system while each hdd has a fan as well as the memory and cpu.
The issue happens with every media player I have found. So far, it has not happened when watching DVDs.
I can play Unreal with no issues, the board and vid cards run great.
I ran memory testers and found no issues.
I have a 600W power supply and I already tried it with one vid card and as few accessories connected to it as possible, the system still froze.
I set the board back to its default values, but it did not help. I never changed any of the voltages or speeds to begin with.
I tried disabling all unecessary background applications including the AV and firewall but it did not help.
I have run scans for malware but nothing was found.
I have reinstalled windows 3 times and the problem keeps coming back.

I did notice the available RAM was way down to 2.75GB out of the actual 4GB, but that is the wonderful winXP ram issue that many ppl have to deal with. there is plenty of RAM available when it crashes so I doubt this is the issue.

i have checked with nVidia but they have 0 support. they expect their customers to buy their defective junk and wait patiently for a fix. i dont have that kind of time.

if anyone can help me, it is much appreciated.

wht abt ur hdd hav u checked it for bad sector ?

if hdd is not an issue try for bios update of ur mainboard...

thsi mainboard was updated with everything i could find, i believe that included the bios.

i did a defrag on the c drive, but i have not yet ran a checkdisk. i can try that, but a bad sector shouldnt cause a system freeze as far as i am aware. plus this happens with almost every movie file i have, on 3 different hard drives, 1 external. the odds that every file has a corrupt sector is unlikely.

wht the format of ur movies ?

mostly AVI, some MPG, WMV, and DIVX

all have experienced a freeze at some point, and ive tried using every player possible, no change.

wht u could check is ur player gets hang or ur pc gets hang
check by ctrl alt delete in processes check for cpu usage


is 100% ?

i tried that plenty of times, its a complete system hang because the mouse is unresponsive and ctrl+alt+del doesnt work either. no bsod either...

i like to ask 1 quick question is ur motherboard in warranty if yes
then plz send it for replacement prob is in ur motherboard ...

You're not the only one with this problem. Seems it has something to do with the 750i/780i chipset.
Type in artifacts 780i mediaplayer in google and go to the first hit (evga forum).
I also got it sometimes with my 750i msi p7n.