我想通过该程序安装 Intel Linux 显卡驱动程序，但每次我尝试安装它们时都会出现此错误
W:GPG error: https://download.01.org Ubuntu Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 8D8847D52F4AAA66
W:Failed to fetch http://ppa.launchpad.net/openshot.developers/ppa/ubuntu/dists/raring/main/binary-i386/Packages 404 Not Found
E:Some index files failed to download. They have been ignored, or old ones used instead.
我该如何解决; 我真的很想安装它，这样我就可以在 Steam 上玩游戏了。
处理器：Intel® Celeron(R) M CPU 440 @ 1.86GHz
显卡：Intel® 945GM x86/MMX/SSE2
32 位 Ubuntu 13.04