[Thad E Ginathom]

I have integrated graphics, and, not being a game player or an avid movie watcher, it is plenty for me, but I'm still curious...

My motherboard supports something called CrossFire for add-in graphics cards. I understand this is a way of closely coupling the two cards?

[ByDesign]

Originally Posted by mercedised

Hello, Could you explain how the use of 2 graphics card will help, Is there any provision of interfaced graphics cards which could use each others memory and yet the output is single. (to the monitor)?

Also which graphics card will be good under 7K Rs? I am a Nvidia fan, but would'nt mind trying ATI either.

These are good budget cards. When I got the 5770, I paid 9,900 for it. Its dropped to 7k now. Brilliant bang for buck. And for games like Mafia 2, its superb. Plus if you're not going to play on my resolution, i.e. 24 inches at 1920x1080, almost every game should work on highest settings and decent frame rates.

1. MSI R6670-MD1GD5 Graphic Card

2. Sapphire ATI Radeon HD 5770 - 1GB

3. Sapphire Radeon HD 5770 - 1GB ( Vapor Edition )

Originally Posted by Thad E Ginathom

I have integrated graphics, and, not being a game player or an avid movie watcher, it is plenty for me, but I'm still curious...

My motherboard supports something called CrossFire for add-in graphics cards. I understand this is a way of closely coupling the two cards?

Since both of you asked the same question, 'Crossfire' or in Nvidia's case 'SLI' is a multi GPU solution for a single computing machine. You basically couple 2 or more (I've seen 4 in one case) graphics cards if your motherboard supports it. Yes, this is more for hardcore gamers who want butter smooth frame rates at surreal AA and AF rendering levels. These extreme machines also end up producing a lot more heat, so you'll need very decent cooling on your machine.

Furthermore, you need a high end motherboard and CPU and ram, if you want to make use of CF mode. There's no point having 2 graphics cards, and a mediocre CPU and low RAM and an even slower motherboard.

For watching movies, and just surfing the net, general computing i.e. office etc. inbuilt graphics is good enough.

Hope this helps!

[anku94]

Originally Posted by mercedised

I want a 2GB graphics card, and my current graphics card is only 1 GB, then instead of buying a new 2GB, I could go for 2*1GB? (ofcourse there will be difference due to hardware limitations of different cards). But, talking roughly in both the cases the outputs should be very similar. (for say both have DDr3 or DDr5)

ByDesign has explained it very well, but there's one more thing, the two cards should be same model, although manufacturer can be different. You can pair a MSI HD6850 with a Asus HD6850, but not with a 6870. As for will that work if both cards have different memory capacities, I'm not sure, but I think it should, provided other things are same, although it's likely the 2GB card will be considered a 1GB card, and the extra 1GB of Video RAM will go wasted. As for whether it will work if you pair a DDR3 version of the card with GDDR5, I don't know for sure, but I don't think they'll work.

There's one more thing to consider - lanes. Motherboards support a limited number of lanes, 16 lanes per card gives best performance. But some chipsets like P67 come with only 16 or 20 lanes, in which case if you intend to use two cards in CrossFire/SLI, you'll have to run both with 8 lanes each, or three cards with 8 lanes, 4 lanes, and 4 lanes. 8x performance is about 0-5% lesser than 16x performance, and 4x performance is 5%-15% lesser than 16x.

Originally Posted by PatienceWins

2500K is a good suggestion as I am going for seperate graphics. Let me see the price difference.

Price difference between 2400 and 2500K is approximately 2k, so difference between 2500 and 2500K will be less than that.

[mercedised]

@bydesign and anku94:

My question remains unanswered? Will the two cards that we use get interfaced automatically and whether they increase performance as compared to the single card for single output?

Let me be more clear on my question: Whether 2 cards increase say gaming performance? and if so then the answer is both the cards communicate at the same time with processor and each other. or its good to purchase single but heavier card?

[anku94]

Originally Posted by mercedised

@bydesign and anku94:

My question remains unanswered? Will the two cards that we use get interfaced automatically and whether they increase performance as compared to the single card for single output?

Let me be more clear on my question: Whether 2 cards increase say gaming performance? and if so then the answer is both the cards communicate at the same time with processor and each other. or its good to purchase single but heavier card?

Yes, there will be a very significant performance gain. With drivers becoming better, a 90-95% increase in performance isn't uncommon. The two cards are joined using a CrossFire/SLI bridge. Performance is almost doubled.



The ribbon like thing connecting the two cards in the above pic is the bridge. Two are used in this pic, but only one is required.

For low and mid end gaming (budget less than 20k for graphics), CF/SLI doesn't make any sense economically. Reason : expensive motherboard, beefier power supply, heat management, potential driver problems (getting uncommon by the day, but some still persist).

For high end, CF does make sense, or is the only option. For example, AMD's fastest card is HD6990. It consists of two of the GPUs used in 6970, but at lower clock rates to control heat. SLI 6970 is the better option because

1. In this case, the heat produced is very high, and it's easier managed with two 6970s and not one 6990

2. Using two 6970 fans produces lesser noise than a heavy duty 6990 fan

3. You don't suffer the limitations of 6990s lower clock rate.

4. 6970 SLI is actually cheaper than 6990 (by $30 or so).

Hope this answers your doubts.

Bottom line : Performance is doubled (1.8x-1.95x) with two cards, but not necessarily tripled by three cards, it's more like 2.5x with three cards. So a single beefier card the better option ? Mostly - yes. Extreme end - no. If you want more performance than the flagship cards (Want to game on 3 or 6 monitors), SLI/CF is of course, the only alternative.

[mercedised]

@anku94: Thanks that really helped and the doubt is cleared now. Just another thing that comes to my mind is should the graphics card also be compatible for double interfacing? I mean that could we use any model graphics card as dual? or there are particular models that support for this.

[PatienceWins]

Dealer does not have Gigabyte H67 UD2H B3 rev 1.1. I will be going for i5 2500 or 2400 processor. Is there any other motherboard with HDMI port?

Asus P8H67M_PRO seems to be a good one.
http://www.asus.com/Motherboards/Int...55/P8H67M_PRO/

[ByDesign]

Originally Posted by anku94

ByDesign has explained it very well, but there's one more thing, the two cards should be same model, although manufacturer can be different. You can pair a MSI HD6850 with a Asus HD6850, but not with a 6870.

I might disagree here. You can couple any ATi card as long as it's in the same sub series. Here's what you can learn from the Wiki Article on CF:
Advantages

• CrossFire can be implemented with varying-GPU cards of the same generation (this is in contrast to Nvidia's SLI, which generally only works if all cards have the same GPU). This allows buyers who have varying budgets over time to purchase different cards and still get the benefits of increased performance. With the latest generation cards, they will only crossfire with other cards in their sub series. For example, GPU in the same series can be crossfired with each other. So a 5800 series GPU (e.g. a 5830) can run together with another 5800 series GPU (e.g. 5870). However GPU's not in the same hundred series cannot be crossfired successfully. (e.g. a 5770 cannot run with a 5870)

Originally Posted by mercedised

@anku94: Thanks that really helped and the doubt is cleared now. Just another thing that comes to my mind is should the graphics card also be compatible for double interfacing? I mean that could we use any model graphics card as dual? or there are particular models that support for this.

This is an interesting question. There are certain games that have an option to run optimized on dual GPU mode. So you'll actually see an option in the graphics section that says "Crossfire" or "SLI". That's when you'll see real good performance increase.

What I've also read about is cases where the game isn't engineered to recognize dual graphics cards and not really react to them. In which I mean, there won't be a big increase in game performance. There are known to be bugs in CF'ing two cards. But there's no such evident risk involved. It's a fun thing to do. Just make sure your cabinet gets loads of cross ventilation and has a decent cooling system.

Two your other question, any new cards according to the wiki post I posted here should be compatible. There are known cards in varying budgets that are known to perform exceptionally well in CF mode, mine being one such case. But then again, also know that sometimes, getting two cheap cards in CF mode, might work out worse in terms of money and performance as compared to a single good card for a marginal cost increase. Again, from my experience, CF'd 4850's and 4670's are pretty brutal. For a slightly higher budget dual 5770's are monsters My opinion? Stick to a single high end card (10k +) or a mid range CF only. Don't get two cheap cards. You won't benefit either way.

[mercedised]

@bydesign: Thanks. I currently have the Nvidia 7200 GS which is lying in junk due to the jamming of its fan. I am now looking for another card, I have heard that Intel too produces graphics card, apart I am a Nvidia fan. Which one should I go with the new Core i7 2600K?? Ati or Nvidia? budget under 7K.

[cranky]

Apart from Metro 2033, any card ~15K can play any game at full graphical quality at 1920x1080.

Multi-GPU only makes sense when you have the real estate for it. The instances are 4M display (2560x1600), multi-monitor and 3D.

Most regular LCDs cannot render more than 60fps so all frame rates above that are a waste anyway.

[anku94]

Originally Posted by ByDesign

CrossFire can be implemented with varying-GPU cards of the same generation (this is in contrast to Nvidia's SLI, which generally only works if all cards have the same GPU). This allows buyers who have varying budgets over time to purchase different cards and still get the benefits of increased performance. With the latest generation cards, they will only crossfire with other cards in their sub series. For example, GPU in the same series can be crossfired with each other. So a 5800 series GPU (e.g. a 5830) can run together with another 5800 series GPU (e.g. 5870). However GPU's not in the same hundred series cannot be crossfired successfully. (e.g. a 5770 cannot run with a 5870)

That's something I didn't know. Thanks.

Originally Posted by mercedised

@bydesign: Thanks. I currently have the Nvidia 7200 GS which is lying in junk due to the jamming of its fan. I am now looking for another card, I have heard that Intel too produces graphics card, apart I am a Nvidia fan. Which one should I go with the new Core i7 2600K?? Ati or Nvidia? budget under 7K.

Intel does not make discrete graphics cards, just the on-die graphics for its processors, they're trash for most purposes (except the transcoding capabilities of HD3000 on Sandy Bridge, which are super).

For your budget, the best card is AMD HD5770 (AMD bought ATI some time ago). Get the cheapest manufacturer you can get, as long as its MSI, PowerColor, Asus, Gigabyte or XFX. I've read about some issues with HIS, so it's best to keep away from that brand.

Originally Posted by PatienceWins

Asus P8H67M_PRO seems to be a good one.
http://www.asus.com/Motherboards/Int...55/P8H67M_PRO/

Yes, I googled a bit and did not find any problems with the board. So if its specifications suit your requirements, you can go for it.

[Aroy]

Here is some information on cross fire. AMD CrossFireX. To run cross fire you require

1. Compatible mother board
2. Power supply with separate power for eacg graphics card
3. Compatible cards
4. Connector cable

[PatienceWins]

The system is getting assembled. Thank you guys for all the suggestions.

Intel Core i4-2400 Sandy Bridge
Asus P8H67-M PRO
Coolermaster GX550 550w Power Supply
Corsair 4GB Vengeance DDR3 1600 MHz
Sapphire ATI Radeon HD6850 11180-00 1GB GDDR5 Graphics Card
Cooler Master HAF 912 Advanced Computer Case
WD Caviar Black 1 TB
HP 24X SATA Internal DVD Writer

[vasudeva]

Originally Posted by PatienceWins

The system is getting assembled. Thank you guys for all the suggestions.

Intel Core i4-2400 Sandy Bridge
Asus P8H67-M PRO
Coolermaster GX550 550w Power Supply
Corsair 4GB Vengeance DDR3 1600 MHz
Sapphire ATI Radeon HD6850 11180-00 1GB GDDR5 Graphics Card
Cooler Master HAF 912 Advanced Computer Case
WD Caviar Black 1 TB
HP 24X SATA Internal DVD Writer

Since you are spending so much (i4 should be i5??), why not get caviar black 2 TB instead of caviar black 1TB. AFAIK, 1TB should be 4-4.5K and 2 TB around 7.5-8K. I have both and there is a very significant performance superiority of 2 TB over 1 TB. Alternatively, get a small cap SSD for boot/OS and a conventional Seagate 1TB HDD.

[PatienceWins]

Originally Posted by vasudeva

Since you are spending so much (i4 should be i5??), why not get caviar black 2 TB instead of caviar black 1TB. AFAIK, 1TB should be 4-4.5K and 2 TB around 7.5-8K. I have both and there is a very significant performance superiority of 2 TB over 1 TB. Alternatively, get a small cap SSD for boot/OS and a conventional Seagate 1TB HDD.

I went for i4 as there is 1k difference between i4 and i5 and the performance difference seems to be very negligible (3.1 vs 3.3) as per the reviews.

I got caviar black 1 TB for 4.7K. 2TB was close to 8k. 1TB is more than enough for my requirements now, I also have a 500GB seagate. I did not know about the performance superiority aspect.

Thanks for your feedback.