As a college student paying my own way it's hard for me to hop on this SLi bandwagon. I do see the performance gains and yes it will be the future but as for now I just cant see spending $200-400 on a GOOD SLi compatible card right now.
I do plan on building a new system but it will be AGP based. I do a fair amount of gaming but not enough to warrent that kind of system. Most of my time spent on the pc is listening to music or watching video, and stuff like this. I get into a game of Day of Defeat for a while but I'm getting 30-60fps (sierra style mind you) with my current system.
AMD XP2400+ @2.15GHz Extreme Volcano 12
512MB RAM 80GB WD Caviar
Shuttle AK39N 9200 @ 297/243(simple fan mod)
I built that in 2003, the year I graduated high school, and it's run most of all the games I want to play just fine. I bought and built it mostly because I was still using a 450 K6-2. (Oh the good ole days~~)
My next rig won't contain a dual core processor, SLi chipset, or oogles of ram either, just something that'll run my games/music/video just fine. Seriously, I still go for a game of Quake III now and then and take Star Craft out for kicks.
I hope most of you remember the VooDoo series of cards and their last 2 cards the 5500 and the 6000(Rare). If you recall the 5500 had dual processing chips, the board was huge, but it ran every game out there almost flawlessly. Don't even think about the performance overclocked. That's what I see NVidia implementing today. A way to add dual chipsets to increase performance. Yeah it works and it works great, but like all new things it's expensive.
I had a 5500 and gave it to my friend who up until last christmas was still using a 500MHz AMD and that card. He literally outpaced 1GHz Intels with that system. Then I gave him my 1st 2400+ and an ECS board. He got a Radeon 9800 256Mb card 1Gb RAM and ran Doom3 with all of the settings on high.
The Socket 462's still have some bang to em and even though the new cards offer more bandwidth, it doesn't all get used. Sure the x16 on the SLi provides more, but does it ALL get used? No, it doesn't. Games haven't been written to use the full memory bandwidth. The data is sent out so fast that the memory
maybe gets 75-80% filled before the pipelines have already sent the data out. What slows the video down is the rest of the system. You have to take into consideration the bus between the slot the memory and cpu speed. Not to mention the operating system and tasks running.
The 7800 GTX has 41.6GB/s of memory bandwidth (
http://www.bfgtech.com/7800GTX_256_PCIX.html), now tell me, which system can actually move that amount of data in a single second? The newest SATA hard drives only move 3GB/s (
http://www.sata-io.org/3g.asp), the latest processors move around 14.4GB/s (
http://www.amd.com/us-en/Processors/ProductInformation/0,,30_118_9485_13041^13076,00.html). The newest RAM DDR2-600 bandwidth is 9.4GB/s (
http://www.xbitlabs.com/articles/memory/display/ddr2-ddr_3.html). You could just add that all up and say total bandwidth is ~27GB/s but still that's no where near the card specs. Why push the cards to move data faster if the bus speeds can't keep up?
It's not just video card performance but the way it's implemented, and SLi does a fine job of putting it all together. Like I said, Pci-E is the next generation and maybe one day I'll get a setup that has dual cards but as for now I'm going to stick with good ole AGP.
Oh here's some stuff on the Crossfire...
http://www.pcper.com/article.php?aid=168&type=expert
Rig plans:
Aspire Turbo Blue Full Tower Alluminum Case 500W PSU
Asus A8V Deluxe
AMD 64 3800 Venice
1GB 2x512 Patriot or Geil RAM (Depending on price)
WD 200GB SATA HD
Radeon X800XL
Kingwin AWC 3000 Cpu + VGA Cooler