Is it my graphic card or monitor?

[noobsorry]

sometimes when i watch video at youtube... i can see some black line then it will disappear again and it only happen when i fast forward the video or pause it for so long and play it again... the black line or sometimes white just appear when something is moving.. i know its not the youtube player fault as when i play the part again there will be no black lines ..
the black line kinda look like this...
http://i672.photobucket.com/albums/vv89/hidros16/sd.jpg


sometimes when i shut down my computer and start it my monitor will say monitor not responding and after a while it will start but all the programs will load slow and when i play some video the audio kinda skipping. .? lets just say broken sound... of course video 2 is bad will have lots of black lines .

and when i restart my computer sometime it will say monitor not responding and just stay black ..

 

[monsta]

Sounds more like a graphics card problem to me , could you tell us your system specs?

 

[noobsorry]

vista home premium 32bit
intel(r)core(tm)2 duo cpu e8500 3.16ghz-3.17ghz
memory(ram) 2047mb
nvidia geforce 9400gt

my monitor is-IODATA lcd-mf221x

my monitor and comp is 2years old i think.. and i use it a lot i mean 12-16 hours a day sometimes i forgot to turn it off so it will run 2-3days..

 

[amuffin]

It could be over heating, take a can of compressed air and blow the card out. There will most likely be some dust.

 

[noobsorry]

yeah i don't think its overheating cuz its so cold here ... and it will happen even after i shut down my comp and let it rest for 7hours and start it up .. sometimes it will happen monitor says not responding or not receiving signal .. dont know what it say but i know its something like that as its in japanese

 

[vrumor]

Just cause its cold outside, doesnt mean your PC is running chilly Download hwmonitor from CPU-ID and let it run and monitor temps in your PC and GPU while you use it for a day and see whats the highest temps it gets to. Will record, low, high and average the values, handy program.