computer keeps crashing

[crashtested]

Hi, hope someone can help....
Every time I turn on pc all is ok and google homepage loads but when I type something and hit enter everything freezes, then the screen goes black and monitor says no input signal. The drive still rattles away , green light on, red light blinking. After turning off and repeating sometimes it happens again, always at the same point. It can take 2 or 3 attempts but then all is ok. Also I have small horizontal lines appear randomly on screen about the width of a cursor but half the lenght, not my monitor at fault cos they scroll.
Anyone please?

[RATTER15]

Does it only happen whilst online to google, have you tried starting PC without logging on to internet?

[crashtested]

Hi RATTER
PC will crash straight away if AVG downloads updates before I have a chance to do anything, working offline is ok though.
I use google as my home page and accessing this is ok.
If I try to access another web page from here pc crashes!

[RATTER15]

Then just uninstall AVG and see if all works without it. then you can either download AVG and reinstall it again or find another anti virus programme. Also delete all cookies and history files.

[crashtested]

I'm not good at explaining things but I'm sure AVG isn't the problem, maybe the hard drive is on the way out?

[RATTER15]

If it is the the hard drive, why doesnt it crash when you are not online, I doubt if it is the hard drive!!

[redmug100]

Possible solutions - update graphics card driver, try a different keyboad plug ps2/usb, check your power supply is adiquate/working propally

[crashtested]

symptoms persist despite all efforts. Nothing else to do but take out both hard drives and smash 'em up with a hammer, then throw this pile of cr@p in the nearest skip.

[crashtested]

Yes redmug, removed graphics card and all is well, it is a 2nd hand one someone fitted for me as a temporary measure, all thats written on it is GV-AF64D REV 2.0
A google search turned up a mention of it in a german forum but no luck at all finding drivers. Thanks for your help.