For the 2010 1156 platform, the following processors are vPro-capable:
Core i5-650, 660, 670, 680
Core i7-860, 860s, 870, 870s, 880
Executive DQ57TM Desktop Board + ATI 4350 or similar / I7 870 (Support for up to 16 GB)
For the 2012 1155 IVY platform, the following processors are vPro-capable:
i5 3570 (hd2500)
i7 3770 (hd4000)
For the 2011 1155 SANDY platform, the following processors are vPro-capable:
Intel Core i5-2500 (Max TDP 95W, HD3000), i5-2400S (65W. HD2000), i5-2400 (95W, HD2000), and i7-2600 (95W, HD3000).
Two 1155 boards, 1 MITX and 1 MATX
MITX: (only PCi 2.0)
INTEL DQ77 mitx S1155 Q77/vpro//USB3/Mini-ITX/bulk (Support for up to 16 GB)/dual lan/hdmi/dp4 usb3/ firewire
Socket 1155 Mini-ITX Motherboard with vPro Remote Management
MATX Dual lan / link aggregetion and all features
Intel Desktop Board DQ77MK (Support for up to 32 GB)
Read up on V-PRO
Android Vpro APP
Msata SSD roundup:
lian li itx q05 case
mitx, thin, msata, i7 3770 or i7 3770s, check out that cooler to. this is the corporate pc of tomorrow.
The Case for Thin Mini-ITX and the Intel DQ77KB - brycv.com
In order to build a vPro Capable PC you need 2 building components:
1.vPro Ready CPU (i5 or i7 mainly Standard and Low Voltage models with S designation) like i5-3570, i5-3470s, etc
2.Series 6 (DQ67EP, DQ67SW) or Series 7 (DQ77MK, DQ77KB) Executive Intel Desktop Boards or Q67 - Q77 in general.
Thus your findings are correct. Core i3 are not capable of supporting vPro even if you install them on a vPro Capable board.
You need both building blocks to be vPro ready.