Posted 08 March 2016 - 12:16 PM
You cannot crossfire between pcie and PCI. With some motherboards you can crossfire the pcie video card with the onboard graphics as long as it's no more then a series newer then the onboard.
You can run multiple video cards on a board with one pcie and the rest PCI but you cannot crossfire they will all run separately.
The only way to get a performance increase running dual cards with a system like this is with Nvidia. You set the nvidia PCIe card as the primary, and put in a PCI card and set it up as a physX card. I do not know how to do this or even if you still can (you could at one point) but honestly a crossfire enabled motherboard will likely give you better performance, and they're not that expensive.
Primary system: Motherboard: ASUS M4A89GTD PRO/USB3, Processor: AMD Phenom II x4 945, Memory: 16 gigs of Patriot G2 DDR3 1600, Video: AMD Sapphire Nitro R9 380, Storage: 1 WD 500 gig HD, 1 Hitachi 500 gig HD, and Power supply: Coolermaster 750 watt, OS: Windows 10 64 bit.
Media Center: Motherboard: Gigabyte mp61p-S3, Processor: AMD Athlon 64 x2 6000+, Memory: 6 gigs Patriot DDR2 800, Video: Gigabyte GeForce GT730, Storage: 500 gig Hitachi, PSU: Seasonic M1211 620W full modular, OS: Windows 10.
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