Hello peeps, thansk for advance for any helpful responses. Recently I had my power supply fail on my PC and from reading around I understand that if not caught early enough this can cause problems to other hardware, like the CPU or the RAM. I thought I had caught it and replaced the PSU however since I have I have been getting a lot of CRC errors/failures on downloaded rars. At first I thought it might have been a couple of dodgy SATA cables I bought(which I added when I replaced the PSU) not transferring the data properly to the drives, but I tried the same download to an external USB harddrive and was getting the same errors. So Im wondering is there a recommended program to test the ram for errors that could be causing this, or does anyone have any other idea of what could be causing it before I throw the PC out of the window. PS I have successfully got the download to save successfully to the same USB external drive on my second computer (a laptop). PPS Just remembered should also add I have been having random reboots and also failures when transcoding/recoding .mkv files since the PSU failed (this is using PS3 video 9, but ffmpeg keeps running in the background).