Nvidia 8400/8500 SLi???

Question

Hi, i am wondering if running two nvidia 256MB 8400GS or two 8500GT in SLi mode would be better than a single Nvidia 8600GT? Also would it be future proof and good enough to run directx10 games? Also i have a 530 watt power supply so is this enough for 8400 or 8500 SLi???
Thanks

Answer 1

In order to understand what will be faster you need to understand what makes the card faster and why...

There are many things that will determine the speed of a video card. The number of pipelines/unified shaders, the speed of the processor, bus bit width, memory speeds, bsp's, plus the overall architecture of the card itself!

A lot of people only look at whether it has GDDR2 vs GDDR3 or the speed in Mhz, but this is only half the equation! The reason memory is rated is because it's how fast it can communicate with the processor - and one of the most important factors!! You must also look at the bus width (measured in bits). I've seen a lot of people in this forum suggest to buy the one only with faster ram, you must take the ((speed of the RAM) * (bus width) / 8)) So, if a card has GDDR3 running at 1600Mhz and a bus width of 256-bits you get 4,096,000 then because it's in bits, you must divide by 8 (8bits = 1byte) you get bandwidth of 51.2GB/sec...

The processor technology is also very important, a lot of people will look at an 8400GS for example with only 16 unified shaders, GDDR2 and a 64bit bus and try to compare it with a 7600GS with 12 pipelines, GDDR2 and 128bit bus - effectively doubling the bandwidth - and say that the 7600 is better. When in reality the 8400 will smoke the 7600 in newer enviroments simply because of the GPU's design. It enables DX10 capabilities, has more 4 extra unified shaders vs pixel pipelines, and a BSP (bitstream processor). So if you were to connect an HD DVD or Blu-Ray drive your 8400 would be able to play it without a hiccup, where the 7600 wouldn't know what to do with it and send it to your CPU and would barely play!!

SLI is a great technology don't get me wrong, however you don't fully get 2x the performance. In some instances you may only recieve a 10% increase! For Ex: say you're playing a racing game, one video card has to render the bottom half of the screen where all the action is and max's out the card, while the other card is rendering the top half where there are only clouds and the card only runs at a 5 or 10% load...

Not to mention, you don't want to max yourself out right away -(2) 8500's might be ok for now, but what will happen down the road when games become more intensive and you have to upgrade? You'd have to remove both cards! I'd recommend buying an 8600GTS for appx the same price which will give you more speed than (2) 8500's and give you a free slot to install another down the road if you need to!!

BTW you should be fine with power - I'm running an 8800GTS with a 500W Enermax, but then again it all depends on how much power you make at 12V...

I should also mention that you can not run the 8400 in SLI - there is no where to plug in the ribbon cable... It was designed as a low-end replacement for onboard video only.



BTW - the comment about DX10.1 is total BS! Any card that is DX10 compatible will work, and DX10.1 only adds minimal instructions that no one will ever use or notice. Nearly every single game maker on the market has already made a statement that it's a waste of their time and money to develop their games for DX10.1 because 99.9% of their client base will only have DX10 cards. Card manufacturer's have also made statements about how ludacris DX10.1 is and that they will not focus on building their cards to those standards either - you need to learn your facts!!


You're right... a good 7600GS will beat the 8400 in most benchmarks, but I'm just trying to make a point that there are a lot more factors than memory speed and gpu speed!

As far as the 8600GT being faster you're 100% right - however the GTS (especially the 512MB) is much better for only a little more money. Well worth the investment over a GT if you ask me!

Answer 2

Everyone has an opinion, the great thing is that there are benchmarks out there that give actual numbers on performance. And the benchmarks are quite clear, a single 8600GT will outperform 8500 or 8400s in SLI. As for future proof, the 8600GT is an average card, and will give average performance on current games, future games will yield even lower performance. As for what Jonathan said, that was truly a great answer, but I have to disagree on what he said with the 8400 vs the 7600, while on Blu-Ray or HD-DVD the 8400 might be better, for games the 7600 wins easily.

Answer 3

They'll be slower than 1 8600 gt (it even says so in 3dmarks as 80% gain associated with SLI ain't gonna make it 2x as fast to match a 8600 gt)
should run Dx10 games OK you have to lower setting to medium though though try bioshock demo it uses the same engine as gears of war and unreal tournament 3.
Although DX10 is BS just prettier particles and water as these thing don't get adopted fast because developers make games that run on the majority of systems usually so they don't waste resources on things most people ain't gonna see.

Answer 4

You can run those in SLi mode if your motherboard is Nvidia SLi compatible. Yes it would be faster than a single 8600GT.
You'd be able to run DX 10 games fine. 530W PSU may not be enough power. I have a 550W that is SLi certified.

Future proof, NOPE. DirectX 10.1 will add lots of new content for hardware. The 8600 and 8800 series of cards will become obsolete shortly after DX 10.1 comes out.

Answer 5

for high end gaming 2 video cards for Sli mode 1 for the top half and 1 for the bottom half

Answer 6

Go with the double card set-up if you can afford it! You'll have double the number of GPU's! Power supply should be adequate! ;-)=

Answer 7

A 530 watt smps is definitely enough i recommend running the2 8500gt in sli. your'e welcome