Hi. I recently bought the following rig: Phenom II X4 965BE Asus M4A77TD Pro Kingston HyperX DDR3 2x2GB 1600 MHz CL9 2 x HIS Radeon 5770 1GB Corsair 750W PSU Unfortunately I didn't do my research regarding the mobo: with CrossFireX it only allows the second card to operate on PCI-E x4. It bothers me that this is bottlenecking the whole gear, so I'm thinking about switching to Gigabyte Gigabyte GA-790FXTA-UD5. It has several benefits over my current mobo (i.e. USB 3.0 / SATA 3.0 support), but most importantly - it supports triple CrossFireX at x16/x16/x8, so I could utilize my 2 cards for full benefit. However, I still have some concerns / questions, namely: - what performance boost (in games) should I expect? Are there any benchmarks that compare these 2 configurations? - will there be any noticeable increase in power consumption? I don't mean the new mobo in general, just switching from PCI-E x4 to PCI-E x16. I assume the PSU I have will handle the change? - and lastly (pardon the noobishnes), since both mobos are 'ATX Form Factor', the new mobo will fit into my Antec Three Hundred case, right ? Thanks in advance for all the help.
Hey man welcome at Guru3D, With a 5770 in CFX you will see a small performance drop with one card at 4x, but really we are talking maybe 5% to 10% here. A lot of data is transferred over the Crossfire bridge anyways. If I where you I'd just tryout the new setup and then decide wether or not the x4 configuration is limiting you.
Like Hilbert says its only going to be a small performance drop. I'm moving from X48 board at X16/X16 to a P45 at X8/X8 which I'm ok with.