dividebyzero
Posts: 4,840 +1,271
@Leeky
I don't think you'll see any big performance increases with more mature drivers. For all the hoopla surrounding driver releases they never deliver across the board sizeable gains. What I think you will see is a more consistant performance in relation to crossfired 6970's. The 6990 will never beat the dual card setup simply because it is clocked 6% lower in core/shader and 10% lower in memory. These lower resources seem to be mitigated slightly by the better performance offered by the 6990's internal bridge chip over the conventional Crossfire connector - I would stress that this is my observation and not an established fact, although the Crossfire ribbon connector does have potential for bandwidth limitation.
Dual cards still have more downside than upside as far as I'm concerned.
Driver support tails off considerably quicker for dual-gpu cards,
If a game has a SLI/Crossfire driver glitch then switching out of multi-gpu mode is painless if you're using two discrete cards.
Dual-gpu cards traditionally have higher RMA and failure rates. They are more complex, have to handle higher voltages and heat output. A cracked solder joint on a duallie for instance presents a bigger user problem than the same scenario on one of a pair of single-gpu cards.
Dual-gpu cards carry a price premium for the given performance-partially due to manufacturing complexity, partly due to the binning process needed to identify suitable gpu's, and partly to keep customer demand down, since duallies aren't money spinners and an AIB will make more profit from selling two single-gpu cards.
With regards this particular dual-gpu card...it has the potential to become a white elephant if AMD and their board partners don't clarify the warranty status of the card. You will note that it isn't being offered for sale in a number of large markets where you expect it to sold. Scan in the UK, Newegg in the U.S. being prime examples. AMD or the AIB's will simply have to eat the any losses incurred -and that includes system failures due to over-current draw or recall the card and lock the BIOS down to 830MHz/375w -which should be it's death-knell since anyone buying this card is certainly looking at overclocking and benchmarking.
Economically (I'll use Overclockers.co.uk for costings since they have most of the UK's 6990 stock) and using like-for-like comparison
HD 6990 is £557.99 inc VAT (cheapest price on the site)
or 2 x HD 6970 (at £264.98 inc VAT ea. £529.96
or 2 x HD 6950 2Gb (at £209.99 inc VAT £419.98
The 6990 can be overclocked to ~920 to 950MHz and 5200-5400 memory before noise levels start playing a significant factor. Tweaktown managed 1000 MHz core at the expense of 100% fan speed and 90dB - a noise level that probably exceeds most developed nations guidelines for preventing industrial deafness.
Dual 6970's can clock higher in general -the caveat being that stacking the reference cards without a spare slot between them raises temps considerably, so either three slots between PCIe x16 or at least a non-reference cooling card as the primary.
Dual 6950's of course can be unlocked to 6970 specification, although they can lack overclocking headroom in comparison with the "real" 6970 - but for £100+ saving you can't have everything.
I don't think you'll see any big performance increases with more mature drivers. For all the hoopla surrounding driver releases they never deliver across the board sizeable gains. What I think you will see is a more consistant performance in relation to crossfired 6970's. The 6990 will never beat the dual card setup simply because it is clocked 6% lower in core/shader and 10% lower in memory. These lower resources seem to be mitigated slightly by the better performance offered by the 6990's internal bridge chip over the conventional Crossfire connector - I would stress that this is my observation and not an established fact, although the Crossfire ribbon connector does have potential for bandwidth limitation.
Dual cards still have more downside than upside as far as I'm concerned.
Driver support tails off considerably quicker for dual-gpu cards,
If a game has a SLI/Crossfire driver glitch then switching out of multi-gpu mode is painless if you're using two discrete cards.
Dual-gpu cards traditionally have higher RMA and failure rates. They are more complex, have to handle higher voltages and heat output. A cracked solder joint on a duallie for instance presents a bigger user problem than the same scenario on one of a pair of single-gpu cards.
Dual-gpu cards carry a price premium for the given performance-partially due to manufacturing complexity, partly due to the binning process needed to identify suitable gpu's, and partly to keep customer demand down, since duallies aren't money spinners and an AIB will make more profit from selling two single-gpu cards.
With regards this particular dual-gpu card...it has the potential to become a white elephant if AMD and their board partners don't clarify the warranty status of the card. You will note that it isn't being offered for sale in a number of large markets where you expect it to sold. Scan in the UK, Newegg in the U.S. being prime examples. AMD or the AIB's will simply have to eat the any losses incurred -and that includes system failures due to over-current draw or recall the card and lock the BIOS down to 830MHz/375w -which should be it's death-knell since anyone buying this card is certainly looking at overclocking and benchmarking.
Economically (I'll use Overclockers.co.uk for costings since they have most of the UK's 6990 stock) and using like-for-like comparison
HD 6990 is £557.99 inc VAT (cheapest price on the site)
or 2 x HD 6970 (at £264.98 inc VAT ea. £529.96
or 2 x HD 6950 2Gb (at £209.99 inc VAT £419.98
The 6990 can be overclocked to ~920 to 950MHz and 5200-5400 memory before noise levels start playing a significant factor. Tweaktown managed 1000 MHz core at the expense of 100% fan speed and 90dB - a noise level that probably exceeds most developed nations guidelines for preventing industrial deafness.
Dual 6970's can clock higher in general -the caveat being that stacking the reference cards without a spare slot between them raises temps considerably, so either three slots between PCIe x16 or at least a non-reference cooling card as the primary.
Dual 6950's of course can be unlocked to 6970 specification, although they can lack overclocking headroom in comparison with the "real" 6970 - but for £100+ saving you can't have everything.