How to identify pre-installed Win7 is Microsoft official original?

How to identify preinstalled Win7 is Microsoft Official original? The details are as follows:

I used to give others when the system is not very careful to install is that version, whether it is Win7 is the official original Microsoft, as long as it can be installed on the line. Oh, this is just before, now install the system will have to pay attention to. To tell you how to identify the pre-installed system is what version.

For now, "Computer City" sales of branded machines (involving a variety of brands, are not listed) installed operating systems mainly: Windows XP, Windows Vista and Windows 7 (with Windows XP and Win7 for many). Brand machine dealers in order to reduce costs, expand Sales, the PC manufacturer of the factory "bare metal" or pre-installed Linux system, installed or modified Tomato Class "Forum edition." This has formed a common strange phenomenon: the installation of "pirated" "genuine" brand machine.

Teach you to tell if pre-installed Win7 is Microsoft's official original

So, how to accurately identify the brand machine stochastic system is the official genuine or "Forum Edition" or "Modified version"?

Brand Machine pre-installed official genuine features:

First, use the "SLIC Tool Kit" Tool for testing:

1, the motherboard BIOS and brand-name machine corresponding to the SLIC 2.0 or 2.1;

2, the stochastic system integrates with the brand machine brand corresponding OEM certificate and OEM SLP key (Note: Windows XP only BIOS SLP 1.0 and OEM SLP key).

Second, the second field of the random system "Installation ID" is "OEM", namely: xxxxx-oem-xxxxxxx-xxxxx (right mouse button/computer or My Computer/properties).

The brand identity is in the computer or My Computer properties. Networking to Microsoft Genuine Verification Center: can smoothly through genuine verification.