post #11 of 11
Memory Sizes:
Can I mix and match graphics cards with different sizes of memory?
While it is not recommended, NVIDIA does offer this flexibility using Coolbits. When purchasing a second graphics card, you should try to match the memory size so that you are ensured full value and performance from your purchase. For example, if your first card is a GeForce 6600 GT with 128MB of memory, you should purchase a second GeForce 6600 GT with 128MB of memory. However, using Coolbits (value set to 18), you can force both of the cards to use the lower of the two memory sizes and operate together in SLI mode. When dissimilar memory sizes are enabled to work together using Coolbits, the effective memory size for each card becomes the smaller of the two memory sizes.
Source: http://www.slizone.com/page/slizone_faq.html#c11
Just for clarification. Essentially, only the cores need to be the same. Although it doesn't apply so much now, the 7800GTX 256 and 512MB editions have slightly different chips.
~Kahuna
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System
(11 items)
 
  
CPUMotherboardGraphicsRAM
Intel i7 4790K Gigabyte Z87M-D3H ATi 7870 Tahiti LE  Corsair Vengeance LP  
Hard DriveOptical DriveOSMonitor
Samsung 840 Pro Seagate ST1000DM003 Win 7 Dell sp2309w 
PowerCaseAudio
Corsair AX760 Silverstone  Soundblaster Z 
  hide details  
Reply