I'm Using radeon 6670 gfx card along with my onboard radeon 2100 card.But in the Vision engine Control it doesnt show any option for enabling the amd cross firex.Please your help will be much appreciated. 

 

Quite simply because you can't use Hybrid XFire with that chipset and that discrete VGA card ..

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AM3 965BE / Corsair H70 / 4Gb Corsair XMS3 2000Mhz / GigaByte 990FXA-UD5 / Corsair Force3 90Gb / x2 HD3870 Atomic Edition / x4 1Tb Storage & Momentus XT 250Gb / Sony AD-7700 DVD-RW / Auzen X-Mystique / Enermax INFINITI 650W / Lian-Li PC-7FNWB / Logitech X-530 / Logitech KBoard & MX620 / Logitech C525 / Epson RX685 / DELL U2312HM

So u know which card should i use in order to enable cross fire??

A little info would help a lot. At least what motherboard.

http://forums.amd.com/game/faq.cfm

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MSI 970A-G46/Athlon 260@3.5ghz/2x4870/TX750M/4gigDDR3

Edited: 07/26/2012 at 01:41 PM by Fishman

EDIT: The Radeon HD 2100 IGP came on the motherboards with the 740G chipset.

Hybrid CrossfireX only works on the 760G, 780G/V, 785G, 790GX, 880G and 890GX chipset motherboards.

You cannot run Hybrid CrossfireX anyways, stick with the Radeon HD 6670 that you ALREADY have.

 

Why are you trying to run Hybrid Crossfire when your Radeon HD 6670 is going to be much faster anyways?

Doesn't seem logical to sell the card you already got, and buy a Hybrid Crossfire Compatible card, to get performance that's most likley less.

Not all motherboard support Hybrid CrossfireX, so please indicate which board you have. Additionally, for Hybrid CrossfireX only works with low-end Graphics Cards. Here are a few (older & newer) Combatibility Charts.

Chart 1: 880G and 890GX integrated chipset works with the HD 5450 / 5550 / 5570 / 5670. http://cdn.overclock.net/7/72/72ab03e2_AMD_CrossfireX_Chart_1618W.jpeg

Chart 2: 790GX, 780G, 780V, and 760G works with the HD 3450 and 3470. http://game.amd.com/us-en/content/images/crossfirex/CF_combo_chart.jpg

Your motherboard manufacturer's website / manual should have a list on what Graphics Cards (GPUs) are supported for Hybrid CrossfireX.

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Edited: 07/26/2012 at 02:55 PM by -rascal-

Aye, Hybrid CrossfireX was originally designed back when AMD cards were pathetically weak (HD 2000 series and HD 3000 series), and now, unless you have an APU with Dual Graphics, basically any HD 5K/6K/7K series card will exceed any Hybrid Crossfire performance (except for the extremely low end parts, but those are made for HTPCs). The HD 6670 is mid level performance and has at least twice the performance of a Hybrid Crossfire setup.

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