I purchased the EVGA 04G-P4-3979-KB from Best Buy and was looking to grab another one, but from Amazon to take advantage of the Witcher 3 deal. I noticed that this model is BB only and the closest one on Amazon is 04G-P4-3975-KR. Can you run these cards in sli? I was also looking at the 90-day step up program and wondering if I could switch out the card I have for the same model as the Amazon card.
 
Ken

04G-P4-3979-KB will not SLI with 04G-P4-3975-KR.

xwing210
Thanks for the response, I guess I shouldn't be surprised that companies would try to relabel an older product and sell it under the impression that it is a newer one.

Well, there diffrient boards so they won't work together. I guess they are kind of just changing it a little to get people to buy it. You should be able to find a compatible version on Newegg/Amazon.

Hi xwing210,
 
Yes, you may step-up -KB model cards as long as they are registered within 14 days of purchase or as long as the extended warranty option is purchased on the product.  Please understand that we do try to make it known on which models will SLI together in the 970 series and our FAQ on this can be found at http://www.evga.com/support/faq/?f=59534.   In general it is usually best to get two of the same model cards when using SLI and please do not hesitate to let me know if you should have any additional questions or concerns. chrisb@evga.com 
 

xwing210
I purchased the EVGA 04G-P4-3979-KB from Best Buy and was looking to grab another one, but from Amazon to take advantage of the Witcher 3 deal. I noticed that this model is BB only and the closest one on Amazon is 04G-P4-3975-KR. Can you run these cards in sli? I was also looking at the 90-day step up program and wondering if I could switch out the card I have for the same model as the Amazon card.
 
Ken

I apologize for the confusion. The 3979-KB is a different model than the 3979-KF. The -KF is indeed compatible with the 3975 as listed in the FAQ.

No, the FAQ is indeed correct. The 3979-KF is listed with 3975-KR under the right-hand column, showing they are comp. 3979-KB is listed in the center column. Referring to JerryCan's issue, he has a -KF and bought a 2977 that wasn't compatible. The 3975 he was offered is compatible with the 3979-KF he currently owns. Again, sorry for any confusion!

EVGATech_JaesonW
No, the FAQ is indeed correct. The 3979-KF is listed with 3975-KR under the right-hand column, showing they are comp. 3979-KB is listed in the center column. Referring to JerryCan's issue, he has a -KF and bought a 2977 that wasn't compatible. The 3975 he was offered is compatible with the 3979-KF he currently owns. Again, sorry for any confusion!

If I may make a suggestion, the last two characters in the part number have been used, for as long as I can remember, as defining the warranty. I think it would ease some confusion if EVGA stuck to the MODEL number being the differential between GPU's.