5x1 Eyefinity + AMD 7950 Crossfire

sirv

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Reading the following request: I want one video card short-term (with my existing system). Before July I will buy a new system. I may buy an additional 2 Gfx cards + 5x1 eyefinity at this point, or I may wait out pricing and hold out for up to a year from now. The question is mostly about the graphics card(s), less so about the monitors.

APPROXIMATE PURCHASE DATE: between today and 4 months from now (1st) - ASAP. Between 3-12 months from now for 2nd+3rd cards + eyefinity 5x1 monitors.

BUDGET RANGE: $600 for the first (well technically that's euro's but w/e). Hopefully no more than $600 again for the other two combined. No more than $600 per monitor. Preferably quite a bit less for the monitors.

USAGE FROM MOST TO LEAST IMPORTANT: Gaming - mixed (FPS, RTS, RPG, MMORPG, Racing, ...), watching movies

CURRENT GPU AND POWER SUPPLY: NVidia 8800GT 512mb with 750W PSU. For 3x CrossFire I will buy a new PSU.

OTHER RELEVANT SYSTEM SPECS: Will be the cheapest Intel Ivy Bridge hexacore for the 3x crossfire, for now AMD Phenom 9950. Case is air cooled, about 18 120mm fans. New case will be fewer but should be sufficient

PREFERRED WEBSITE(S) FOR PARTS: Tweakers.net PriceWatch

PARTS PREFERENCES: Not particularly. 5x1 portrait -> AMD; 7950 pricing (especially after a year, for the other 2) seems a lot better; the Sapphire 7950 OC runs very efficiently, cool, and quiet (so I've read). So that's what I'm looking at, but I'm not dead-set on it.

OVERCLOCKING: Not at first, would have to see how 3x Xfire will run the 5x1.

SLI OR CROSSFIRE: YES

MONITOR RESOLUTION: 1card: 1920x1080. 3cards: Hoping for 7200x2560, may need to economize down to 6000x1920 or even 5400x1920.

ADDITIONAL COMMENTS: Must be built for 3card crossfire, eyefinity 5x1 portrait from the start. Because of this, I'm ruling out 3slot cards such as the Asus HD7970-DC2T-3GD5. Along with price/performance, running quiet-ish is a boon. Energy efficiency is of smaller import, but not completely unimportant. I have zero interest in 3x1 eyefinity.

I'm currently looking to buy a 7950 (the sapphire 7950OC looks very nice without me having to mess with it). I would buy one now, then later on would buy two more for eyefinity. A second for the additional average FPS, and a third to up the minimum FPS and reduce micro-stuttering.

I'm [probably - price/quality looks good] looking at 5x Dell UltraSharp u2412m or Dell UltraSharp u2711. 5x U3011 is definitely out of my price range. The big pro for the u2711 to me is the additional pixels (even if I'll have to have the power to push them) and 16x9 - 45:16 (2.81) seems a nicer ratio than 50:16 (3.13). I've been thinking of trying to find a store to check out the u2711, if the anti-glare filter looks okay this would be my prime choice despite the exorbitant price - more than double the u2412m.

The rest of the system is a non-issue, I've already budgeted an upgrade to a high-end intel platform in may (waiting on 22nm; my mind is set on the cheapest hexacore).

Additional Questions:
[ol][li]For optimal crossfire results, you need 2/3/4 times the same card. However, does this mean I would need 3 times the sapphire 7950 OC? Or would it mean I would simply need 3x a 7950? Or 3x a 7950, each with the same core/memory clock rates?[/li]
[li]I've read you can only use one card as output device. So if you have 5 monitors, you need (at least one) card with 5 or more outputs? So I couldn't just buy 3 cards and use 2, 2 and 1 of its displayports?[/li]
[li]How flexible is the eyefinity resolution? Suppose I get 5x u2711 making the resolution (before bezel correction) 7200x2560, but some game brings the system to its knees. How easy (if possible at all) would it be to run at 3600x1280?[/li][/ol]
Thanks in advance.
 

Kari

Splendid
I've read you can only use one card as output device. So if you have 5 monitors, you need (at least one) card with 5 or more outputs? So I couldn't just buy 3 cards and use 2, 2 and 1 of its displayports?
AFAIK that is the case, so for the main card you should try to get one of the eyefinity6 editions if someone actually makes one out off 7950, or something like that.

Changing the resolution shouldn't be an issue as long as all of the monitors support it, so it should be easy to change it downwards..


edit DP1.2 monitors and/or DP MST hub could help you out witht the dp outputs, since 1.2 monitors allow for daisychaining them together and mst hubs let you connect several monitors to a single dp on the card. Sadly neither are available yet... (or at least I haven't seen any)

edit2 22nm hexacore? I thought IB-E was stilll a year away or are they making hexacore for the 1155 socket as well?
 

sirv

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Rumors are out there of a 6mDP 7950, but nothing official yet. If I've read you right, the other two just need to be any 7950?

DP could provide for multiple screens but the bandwidth is still limited. I tried deciphering the wikipedia page on this, but it went over my head. It's probably possible to drive 2 screens of the 1920x1200x24bit Dell u2412m, I doubt it is with the 2560x1440x30bit Dell u2711's.

As for the hexacore, tbh I haven't been following it too closely. If it does take that long I'll either wait or cave for an Ivy Bridge quadcore. I was so rooting for a hexacore with 32gb though. Something to last 3-5 years (except for the gfx card, that's generally 2.5-3).
 

Kari

Splendid

Supports high resolution displays and multiple displays with a single cable
17.28 Gbit/s of effective video bandwidth, enough for supporting 4 simultaneous 1080p60 displays (CEA-861 timings) or 2,560 × 1,600 × 30 bit @120 Hz (CVT-R timings)
hmm yes, looks like it'll only do one 30''er @120Hz (or two 1080p@120Hz; prolly 1200 as well). It's not as usefull as I thought it would be, oh well... :ange:
 

sirv

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However, since both screens I linked (like any other IPS monitor currently out there) only support 60Hz, that actually would work.

In any case, from what I've gathered so far, for optimal Crossfire you just get the same model cards, try and make them similar clock/memory wise and you should be good to go, even if you're mixing a regular one with an eyefinity6 model (or some such). There were other questions mixed in there but that was really the one I wanted an answer to.