Dual cards, power and connectors

[Lavaridge]

I'm building a system around an ASUS GTX 780 GPU which I already have, and want to double-check that it will be compatible both with the single card I already have and with a second I may add in future (because apparently it's cheaper to upgrade by SLIing a second identical card than buying a new, replacement, top-of-the-range future card (although let me know if this advice is untrue)).

Case
COOLERMASTER CM690 MKII ADVANCED CASE
Processor (CPU)
Intel® Core™i5 Quad Core Processor i5-4670 (3.4GHz) 6MB Cache
Motherboard
ASUS® Z87-A: ATX, USB3.0, SATA6GB/S, SLi, XFIRE + **FREE GAME**
Memory (RAM)
8GB KINGSTON HYPER-X GENESIS DUAL-DDR3 1600MHz, X.M.P (2 x 4GB KIT) ATX, USB3.0, SATA6GB/S, SLi, XFIRE
Power Supply
CORSAIR 1000W RM SERIES™ MODULAR 80 PLUS® GOLD, ULTRA QUIET
GPU
2x ASUS GTX780-DC2OC-3GD5

I especially don't understand the specific types of power connector that the cards require, but since PCS would let me build a system with a GTX780 from them I'm assuming the PSU has enough of the right connectors for at least one such card. I'm also not sure if the motherboard can take two large cards side-by-side (although I know the case can fit them). I'm sure these are silly questions and that the cards are probably sufficiently narrow that two can be placed side-by-side in the two PCI-E slots but I want to make sure before I buy. Thanks.

 

[keynes]

Depends on whether you find a gpu for sale once you wish to upgrade. The motherboard supports SLI, not sure about the psu. I would assume it is, just put 2 gtx 780s in the configurator.

 

[mantadog]

Upgrading to SLI may be cheaper if you are able to buy a card in the future, however it will probably be a 2nd hand card if your talking way off into the future. The benefit single high end card option may be more costly, but it may very well outperform the dual card config.

The motherboard will generally fit whatever the board is rated for, ie 2 or 3 way SLI. Most cards now take up 2 slots as a minimum and sometimes high performance coolers push that to 3 slots. Generally your not going to fid your PCIe x 16 and x8 slots right next to each other so the only time you will run into issues would be with additional RAID, wireless or other expansion cards you may be trying to have. For most that is not an issue though, buy a SLI compatible board and you will be able to run a SLI setup.

The power connectors could be difficult, however as you might expect a couple of solutions exists... Lets say 18 months down the road you need a new standard for connecting GPU's for whatever reason, the standard connectors are now junk for high end cards. You could just buy an adapter that uses your existing available cables to make a hybrid cable that powers the card. You would however be in a much better situation as you are using a modular PSU. You would just order up a new cable, slot it inot the PSU and away you go, you now have the perfect connector.

 

[TheKeir]

If you already own a GTX 780, then buying a second one will give you vastly better performance than a single GTX 780 Ti (in SLI-enhanced games).

As for the power supply - that PSU should come with all the cables you need. I'd recommend dropping it down to an 850W not 1000W, since 850 will easily handle 2x 780.

 

[steaky360]

I would concur with what's been said above, a second 780 is more cost effective than swapping your 780 for a 780Ti in a price/performance point of view. It does come with its own drawbacks (increased power usage and heat) but those are typically easily managed. The 1000W PSU will have sufficient 6/8pin connectors for SLi 680s so I wouldn't worry about those and as Manatadog pointed out in the future should the standard change drastically, there's a descent chance you'll be able to just get adapters and continue using your current PSU. The vanilla 780s require 1 8pin and 1pin power connector [PCI-E connectors] of which your PSU has 8 of.

 

[D1craig]

The next gen of Nvidia cards should be a significant jump from this lot so SLI may not be that great.

I just don't like the idea of SLI/crossfire though so of just try get a single better gpu.

 

[Sleinous]

Depends on whether you find a gpu for sale once you wish to upgrade. The motherboard supports SLI, not sure about the psu. I would assume it is, just put 2 gtx 780s in the configurator.

Totally agree with you, nowadays the problem seems to be finding the same GPU on sale later on in the year as new series keep getting released at an ever increasing rate which makes the EOL for each GPU progressively sooner