Widescreen Gaming Forum

Want to show you guys this quality review from all aspects
http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/41404-amd-radeon-hd-6990-4gb-review-19.html

Is that before or after flicking the "Antilles Unlocking Switch" (that is a manufacturer included feature of the card, but voids your warranty if you use it... strange, I thought things like that were illegal...)?

I"m lazy but whats the price point of two GTX580 vs a single ati 6990?

6900 = ~£550

GTX580 = ~ £400

Therefore

2x GTX580 = ~£800

6990 wins.

6900 = ~£550

GTX580 = ~ £400

Therefore

2x GTX580 = ~£800

6990 wins.

If your going cost alone, if noise is a concern, don't go anywhere near the 6990. Also don't go anywhere near it if you don't have a well ventilated case with high air flow, the card will throw half of its heat back into the case. At least not until some none reference coolers come out for it.

http://www.tomshardware.co.uk/radeon-hd-6990-antilles-crossfire,review-32136-15.html

_________________
: ) Skid : )
My Multi-Monitor Focused YouTube Channel: http://www.youtube.com/c/SkidIncGaming
My Twitch channel which I've been known to stream on from time to time: http://www.twitch.tv/SkidInc
"Imagination is the only weapon in the war against reality."

As long as the 6990 doesn't sound like a GeForceFX or 480 @ max fan when idle, I'm not too bothered. When I'm gaming I've got sound on (usually quite loud) so if the fan kicks up a bit it's not a game-breaker.

Obviously, for others mileage may vary. ;)

As much as I'd like a pair of 3GB GTX580s, even the cheapest are ~£425, so I'm looking at £850 for two. For the saving of £300, the 6990 has got to be really poor in other areas before it looks like a failure. :( ;)

Not while idle but it goes well past the 480 under load, and that's before you flick the overclock switch.

So, what does it take to dissipate the heat generated by a 375 W card?

Apparently, it takes a noise chart uglier than sin itself.

The problem is that AMD doesn’t use a graceful ramp. It instead steps fan speed up and down to address thermal demands. As a result, you hear the board’s cooler accelerating and decelerating like an engine when the driver downshifts coming up to a stop light.

This is something Nvidia put a lot of thought into after getting skewered for the GeForce GTX 480. I dissected a GPU-Z log file taken while just sitting on the Just Cause 2 menu screen and came up with the following:

Up to about 78 degrees Celsius, the Radeon HD 6990's fan spins at about 2180 RPM. We’ll call that the safe zone. Within a minute or so in a 3D application, the warmest GPU heats up to somewhere between 88 and 89 degrees, and the fan cranks up to 2880 RPM. That’s “who played a trick on me and swapped my graphics card out for a GeForce GTX 480?” territory. Both the AMD and Nvidia cards crank out about 51 dB. In order to keep the card at 90 degrees or less, the fan then speeds up to 3600 RPM, or what I call Charlie Sheen F-18 mode.

There’s no excuse for a graphics card to be this loud and, if spinning its cooling fan up to 3600 RPM is the only way to keep the Radeon HD 6990 from overheating, then this product simply isn’t ready for consumption. Because the problem is related to fan speed, there’s a chance an updated firmware could smooth out the way AMD handles heat. Right now, though, there’s no way I’d install one of these things in a gaming machine.

The problem is compounded by the fact that two Radeon HD 6970s in CrossFire top out at 53.1 dB(A) (slightly louder than a single GeForce GTX 480) and two GeForce GTX 570s in SLI max out at 49.1 dB(A)—quieter than a Radeon HD 5970. Both card combinations exhaust all of their air out the back of your chassis, they’re both quieter, and the 6970s, at least, are universally faster.

_________________
: ) Skid : )
My Multi-Monitor Focused YouTube Channel: http://www.youtube.com/c/SkidIncGaming
My Twitch channel which I've been known to stream on from time to time: http://www.twitch.tv/SkidInc
"Imagination is the only weapon in the war against reality."

6900 = ~£550

GTX580 = ~ £400

Therefore

2x GTX580 = ~£800

6990 wins.

Certainly in a "forget everything else but price" analysis. :)

Also SLI NVidia in surround does not have the awful stuttering that CF in Eyefinity does. I ditched my 6950s for 2 580s (and previously my 5970) because of that, never buying CF for the foreseeable future. An awful problem that has no fix. Admittedly not even one gets it/notices it but it is a deal breaker to me, twice bitten now shy ;)

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Dipping bags at Mach1.9

Bleh, apples-to-apples comparison. [H]ardOCP has a much more compelling comparison in my opinion. Average FPS over the course of a gaming session is more important than the peak or lowest numbers

Real World Gaming Performance:

Apples-to-Apples:


And something important you forgot to include: the system configuration.


Looking at the Canucks review it looks as if the power supply they're using isn't powerful enough for the 580s in SLI at least, especially with the CPU overclocked as it is.
The important thing to note about this particular PSU is that its +12V rail is only capable of 80A combined, which means it needs to be outputting maximum power at all times under load to be sufficient at powering these two cards. And as we all should know, the closer a PSU is to its maximum output, the more noise and fluctuation there is and the less efficient it runs.