Need Advice on NEW Maxsun HD6790 Please.

[woody213]

Just giving a little background. Before my purchase I was running 2 Power Color HD6770 Single slot cards in XFire. I was in the right place at the right time and got them from Newegg as OpenBox for $85 each. I figure this was a good deal considering they are still on Newegg for $140+. Anyway I run an open bench case and these cards after an hour of gaming start getting loud. I was looking at the HD6850s on Ebay and stumbled on an auction for a new HD6790 from Japan. (www.maxsun.com.cn). The seller and card were in the US. I got the card for $95 + $10 shipping. Every review I have read on the 6790 has been get the 6850 instead. The HD6850s range in length from 9.5 to 10.75 inches and after looking on Newegg the 6790s seem to have an even broader difference in length. from 9.25 inches and 1 PCIe power connector to 10.6 inches and 2 PCIe connectors (why?). Because of the SATA placement on my board I can not exceed 9.5 inches on the main PCIe slot and 8.5 inches on the second slot or I hit the SATA connectors. Here are my questions please.

Why such a big difference in PCB boards and PCIe connectors? Am I missing something in that these larger units have something that the smaller units don't? I am really curious because this card I just purchased is even smaller. It measures less than 8.5 inches long. The fan runs at ideal at 52 to 57% at 40-44 degrees. Under full load it jumps to 65 to 70% and gets to 58 degrees at most.

I ran some power consumption checks and this card is pulling about 10% more power than my HD6770 was. Way less than the other HD6790 reviews I have been reading.

What cards can I crossfire with this HD6790? Also if I get a more powerful card is better to run the HD6790 as the primary card (PCIe X16) or in the second PCIe 4x slot?

Over all I am please with the purchase. I have only two small gripes. The fan ideal speed (if in case wouldn't be an issue) and the fact that it is not running at the 840mhz as stated on the box and on the website. It is showing under AMD Overdrive as 800mhz.

Any info given would be greatly appreciated.

PC Specs:
Intel I5 2500K
Biostar TH67+ H67 Motherboard
G.Skill Sniper RAM 2 x 4GB.
Corsair Force Series 3 90GB SSD
3 x 1TB Samsung HDs (RAID 5)
KINGWIN Mach 1 1000W Power Supply.
Maxsun Radeon HD6790

 

[Onus]

Crossfire at x16,x4 is not an optimal arrangement. Given that not all games benefit from Crossfire, or have driver issues, I think a single, stronger card makes sense for you.
I don't think a HD6790 is enough of a jump though, at all. It isn't that remarkably different from the HD6770, except it has a 256bit memory buss, vs. 128bit for the HD6770. Something like a single HD6870 would be a much more meaningful increase, or a HD6950.

 

[woody213]

OK, my problem with that is like I said I don't have the room. Both the 6870 and 6950 are 10+ inches long. As for the Xfire boost, I when from 15,600 on 3DMark2006 with one HD6770 to 22,500 with two of them. Individual fps went up as much as 25 to 30 frames. I consider that a big jump from a card that is bottle necked buy the memory interface. Just ran 3dmark2006 on new card and got 18,300. I was expecting a little better.

 

[amuffin]

Your board is probably the problem, also never heard of maxun :O

 

[woody213]

Maybe I worded this wrong. I got the board used, less than 3 months old for $50 on Craigslist. It's by far not the best but you can't beat that price tag. The problem isn't the board or even the video card. I just need advice and info on the PCB boards being used for the HD6790 and what is the best configuration for what I have now. The HD6000 series cards are dropping in price so I can get another HD6790 for under $100 or go with a HD6850 for about $110. I was not sure if these two different cards would work together in X-Fire and which should be the primary card?

 

[Onus]

They will not work together in Crossfire. The cards need to be the same model designation. If one of the cards is slower or has less RAM, both will take on that lesser configuration in Crossfire, regardless of which card is in which slot.