i recently installed vista home premium 64bit on my pc and it was working fine, however it was a little slow because i only had 1gb ddr 2 ram installed, so i purchased another piece of ram and installed it on thu, since this time my PC has been acting up no end. it will stop all of a sudden and the screen will go blank, it comes back after a few seconds with a message display driver stopped working, but has sorted itself ! this keeps happening again and again !
i have tried installing updated driver for graphics card but it says the driver being used is the most upto date available.

has anyone else had this problem and any ideas of a solution ?

Some ideas, 1) verify that this ram is compatible with your system. 2) Try to reseat the ram (remove it and put it back in). 3) Return that ram as BAD. I've done this several times. Yes you can get bad ram, especially if you buy bargain basement priced ram. I hope you saved your receipt.

Basically, when you have bad ram, you receive many different errors. It could be drivers, it could be system files, it could be any application files. This is my opinion. Try those 3 things. I doubt that since upgrading ram, that a driver suddenly went bad on a new machine. Is it possible, YES, but I doubt it.

Yea I would say it's deffinately something with the RAM if it was working fine before you put the RAM in. Something about it is conflicting with your software.

This happened to me before! And for me i had a bad stick. To make sure its the new stick you just bought remove the old one and leave the new one in and then boot back up. if you have the same problem then you already know the answer. if not try putting the new stick of ram in a different slot. i just bought a board that did not like to run on dual channel, or you have a bad main board. then try buying a new board. and on e more thing is check the voltage on your ram and make sure that your board will run on it. some of them are strictly fixed not a variable voltage. If your not to comfortable with buying anew main board that there is a program that you can download that test your ram, but its time consuming, and a little confusing. I'll try and get that to you in the next day or two.