Lenovo Y500 USB boot+ bad Tearing Problems + NVENC + grub/usb boot(fixed but strange)

[Tobias4X]

I am fully satisfied with my Y500 - only one issue nags me

(Y500 - 650M SLI/16 gig ram/ssd replaced with bigger capacity/1TB HDD)

USB-Boot

at the start i could boot from any USB stick or HDD i wanted but then i changed the boot device priority to my currrent USB device at that time to be on top, hoping it would be recognized and booted from whenever inserted at start.. and well it booted and works till today but i NEVER could use any other usb device to boot since then. upon pressing F12 on bootup or recovery key for boot menu i will become stuck if another USB stick is inserted or anything that can hold data in an bootable way. does Anybody knows what could have caused it? and could a bios replacement repair that? i just want to boot normally from all my devices again (usb)

EDIT: flashing the bios didnt help but boosted the speed of my system by 3 times

NEXT:

(i have a linux-windows dualheart thumping under the hood of that beauty so i will describe both)

Windows:

Winamp, Vlc, Adobe media player - you name it - the video tears BADLY. i can hold my finger on the line a video will show a clear rip on always, on beamer, screen and laptop screen (VGA/HDMI dont matter aswell). It destroys any movie watching into an event of watching that single annyoing line not synced. i only get it to work in K-lite codec pack with Vsync and postrpocessing on max.

but yeah you know vlc-the swiss video army knife plays even corrupted files and makes awesome use of strange formats so is there a way to enable something like amd's XINERAMA i loved so much on my old pc? so everything will become ripfree again?

System: Windows 7 professional

All drivers installed and up-to date, only replacement is 16 gig ssd for an crucial 240 GB but the problems were before aswell

Linux:

Kinda the same, only Ubuntu 13.10 on free drivers did a better performance than that but on non-free nvidia drivers its just the same. Even worse Ubuntu 14.04 doesnt support the drivers in any way of free kind, only nvidias own driver works - but surprisingly well, the tearing broke down to a minimum (also it supports backlight change now) so.. yeah i know its the driver but is there a windows solution?

NEXT:

Openbroadcaster + NVENC works very bad despite two Graphics cards bad. justplain bad. the video is nothing more than a pile of artifacts. i would like to use NVENC since it saves some processor runtime and i always appreciate less pocessur usage

NEXT:

Grub.

2.0

legacy.

ANY version wont start from SSD and if started from HDD (after being made bootable by boot-repair) just offers a black screen upon trying to boot windows (and fromm ssd ubuntu aswell). i hear the processor fan heating up and it just seems stuck at booting/loading. strangely the alternative boot loader "LILO - LInux LOader" works without any compliant after some handiwork.

Had anyone ever experienced something like this? also is there a way to change this behaviour? i kinda like Grub 2 and the ... a bit newer design and look it offers than lilo which still is counting 15 mb ram as not given on much PCS... also could relate to my usb boot problem? i dunno

System config:

BIOS: Boot = Legacy, legacy first

SSD/HDD Structure:

SSD : 100 gig linux, 140 gig windows, 10 gig free space

HDD: 200 gig linux - /home | 50 gig linux -/var |750 gig - windows Data/games/downloands n more

A many problems, i hope you guys can help in any way, that would be awesome!

(lenovo just said in the forums "yeah can happen, fine, not our problem since we have your money")