How to voltage mod your GTX400 BIOS and physical mod

This is an easy how to tutorial from overclockers.com guys which allow you to create a modified BIOS file and increasing the GPU voltage to 1.212 V in four steps , also a physical modification in there :
 

"This short tutorial is based on my Gigabyte GTX470 (GV-N470OC-13I rev 1.0), it’s a reference card with a slightly higher GPU clock of 630 MHz. This type of BIOS modification is working on other reference GTX4xx cards like the GTX460/465/480 as well. A standard GTX470 has the max GPU voltage locked at 1.087 V, but there’s an easy way to unlock up to 1.212 V. Here are some steps on how to unlock the max voltage on a GTX4xx GPU."

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Gigabyte GTX470 Mod version Benchmark results:

Almost 6.2k in 3DMark11 @ 920 MHz core
Over 23k in 3DMark Vantage @ 925 MHz core
Over 28k in 3DMark06 @ 925 MHz core