I'm planning on doing crossfire with my xfx radeon hd 7870 doudle d. The thing is, am not sure if i'll be getting the performance that i want with different pci-e expansion slots.
Here's my pc specs:
Processor: Intel Core i5-3550 3.3GHz
RAM: 8GB Kingston 1600MHz
GPU: XFX Radeon HD 7870 Double Dissipation
PSU: Cooler Master Extreme2 625W (I'm planning to change this when i'll crossfire)
Motherboard: Asus P8H77-V LE (http://www.asus.com/Motherboard/P8H77V_LE)
Can someone tell me if i should worry about the performance?
You can most likely run it, but you will take a small performance hit. Not sure how much though. A few sites in the past has done tests using high end cards on PCI-E 1.0 slots with high end 2.0 cards they found something like 5% performance hit or around there when they used it in a 1.0 x4 slot. And that x4 slot should be equavalent to half the speed of a full x16 pci-e slot for max bandwidth. So even taking differences into account I suspect it will still work for a good performance increase but it won't be as good as if you had a full x16 slot as I still suspect something along the lines of 5-10% performance hit.