Help me Choose! R9 390 CF vs R9 295x2

[Christian Pratt]

I'm looking to upgrade from my GTX 760. I found a Sapphire Radeon R9 295x2 for sale for $550. I also found 2 Sapphire Nitro R9 390's for $500. Both look like they are in great condition. Which is a smarter/better buy, please help!

My PSU is a Corsair TX650M which I do not think will support either of these setups?

 

[RCFProd]

You need a quality 850 watts or better to run R9 295X2 or R9 390 crossfire, depending on your processor and motherboard it might even need to be higher. The Corsair TX650M has no chance with these GPU setups.

 

[ko888]

Two SAPPHIRE NITRO R9 390 8 GB is better. Each card has 8 GB of VRAM to work with.

System Power Supply Requirements for two Radeon R9 390 graphics cards in 2-way CrossFire mode
• AMD specifies a minimum of a 950 Watt or greater system power supply. (Minimum system power requirement based on a PC configured with an Intel Core i7 3.2GHz 130 Watt TDP processor.)
• the system power supply must also have a maximum combined +12 Volt continuous current rating of 67 Amps or greater
• the system power supply should also have at least two 75-Watt 6-pin and two 150-Watt 8-pin PCI Express supplementary power connectors. There are some non-reference design cards that require two 150-Watt 8-pin PCI Express supplementary power connectors (e.g. Sapphire R9 390 Nitro).

Total Power Supply Wattage is NOT the crucial factor in power supply selection!!! Sufficient Total Combined Continuous Power/Current Available on the +12V Rail(s) is the most critical factor.

Overclocking of the CPU and/or GPU(s) may require an additional increase to the maximum combined +12 Volt continuous current ratings, recommended above, to meet the increase in power required for the overclock. The additional amount required will depend on the magnitude of the overclock being attempted.


On the Sapphire Radeon R9 295x2 each GPU only gets 4 GB of VRAM to use. AMD specifies a 1000 Watt or greater system power supply that has a maximum combined +12 Volt continuous current rating of 69 Amps or greater and has at least two 336W 8-pin PCI Express supplementary power connectors. AMD has greatly exceeded the power draw allowed by the PCI Express specifications for the 150-Watt 8-pin PCI-E power connector.

 

[Supporter]

so in other words, if you want to drain your town's power grid use amd in crossfire?

 

[Greeko85]

Another thing to take into consideration is your motherboard? Are you able to run crossfire in x8 x8 pr greater or do you have a more "basic" one that allows pcie3 x16 pcie2 x4 setup?
If its the latter then crossfiring 2 390s could result in a bottleneck for the 2ns card due to limited pcie bandwidth