TheDeathEffect

Similar problem here with my e5420 i7-2670qm Win8.1. If egpu is detected on startup, it disables igpu and only outputs video to to external display (no optimus). If it is hot-plugged, I get error 12. If it is hot-plugged with DSDT override (large memory in device manager) I get a black screen. I can move around the mouse, but it constantly returns to the center like the display is resetting. I'll update once I get a better graphics card to test with and finish a raid 0 setup with Win 7. If that doesn't go through, I'm in the process of a DIY USB-powered monitor. Snagged a logic controller board from here http://abusemark.com/store/index.php?main_page=product_info&products_id=47 and an LCD from here http://www.ebay.com/itm/iPad-3-LCD-Screen-replacement-For-iPad-3rd-Gen-Compatible-Screen-/121559909667. Need to make an enclosure for it and it limits me to card with displayport, but we'll see how it goes!

The extra pcie cable is to give a graphics card extra power if the pcie slot alone is not enough. The 8 pin on the EXP GDC is for input from Dell DA-2 (or ATX PSU w/ converter cables because it has reverse polarity to ATX 8 pin pcie, as mentioned in first post). The 6 pin on the EXP GDC is output to graphics card using the included cable. So you should be safe plugging that cable into the EXP GDC and GTX 970 for extra power. The 6 pin pcie with a lot more wires coming out of it is the side that goes into the EXP GDC. .

Would it be possible to solder the connections on a PE4C myself?

Looks like you can still save a few dollars with 6e6e0b on banggood For those of us in the States, the PE4C is available on Amazon (with prime!) for $60 Amazon.com: Bplus: PE4C interface for ExpressCard, PCIe x16 adapter: Computers & Accessories You may want to hold off on the PE4C until after Chinese New Year so BPlus has a chance to address the signalling issue