I understand that, and to some, it may be noticable. It does to some extent help even out frame rates, that I do not deny, however... There are still limitations to how much it truly helps. Bottlenecks aside, not all GPU, CPU, RAM or VRAM is created equal. Which is a huge reason why you should buy matched pairs... But wait, graphics cards don't have matched pairs, so how can you... You can't. Hence why you can have 2 identical cards, from the same manufacturer, run at 2 totally different speeds.
Take my 1080 Ti's for instance, they both ran at similar frequencies and speeds, yet one on slot A always ran 40-100mhz behind the one on slot B, and at first I though maybe it was a PCI-E issue, so I switched them around... The same card ran 40-100mhz slower still. I mean, it still ran within it's stated spec, but it was always behind. The manufacturing dates were on point, so what was it? I'm still unsure. Now that card overclocked like a champ, whereas the other card, meh not so much. Firmware was identical as well. Both ran the same firmware, coded on the same date, and even to double check my work, I reflashed both cards with the same firmware on the same day to no avail. That's why I said earlier, sometimes multiple cards are bad deals. Not to mention the various types of SLI available. You have software based and hardware based. You can put the bridge on or keep the bridge off. But again, that's delving into something that the average user doesn't want to mess with. On top of that, the average person doesnt want to mess with frequencies, voltages, timings, etc of their hardware. Most people want to take it out, install it, and if it works, it works, leave it alone. Then you got silicon junkies like me, that rip shit out of boxes, drop it in, go to the BIOS, and start fucking with vcores, vdroops, multipliers, CAS, t-RAS, t-RCD, and tRP limits. To squeeze ever last drop of performance out of my hardware without doing instant permanent damage to it. Which 8/10 times, I'm successful. There's that 1 or 2 times that I volt too high or too low... And bang! Dead shit.
But why someone would need multiple cards in the first place is beyond me. Again, unless you're running a multimedia platform and you just need a card to handle encoding / decoding or unless you're running a multi-monitor setup, that's all good, but to run them in SLI, honestly, is a waste of time, money, and valuable case space. LOL.
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