Crossfire question

[TheRawkstar]

Hi guys, This is my first post. I use Tom's hardware a lot when i have any computer questions, so i decided to register finally lol.

I am building a new system based on the amd fx line and the scorpius platform. I'm going to be using the amd fx-8120 processor, a 990fx motherboard, 16 gigs of ddr3 1600 RAM and a single Radeon 6970 GPU. I understand this is going to run most of what i throw at it no problem. My question is say I'm looking for a minor increase in performance (~10 fps) can I just throw in any additional radeon 6000 series card with it? or would it need to more exact like only a 6900 series (6950,6970) card? my power supply is not an issue, I'm really only worried about which cards are compatible. Thanks in advance for any help you can provide

 

[amuffin]

I would recommend an intel build if you are going to use a high end system like that. You can only cf in this case a 6970/6970, 6950/6950.

 

[TheRawkstar]

I'm going with the amd fx line for the scorpius platform specifically. I can't get that on intel, and the overclocking on the amd processors is ridiculous. the fx line got a world record for fastest overclock speeds achieved (~8.4 ghz, via liquid nitrogen ) but my build should be able to handle overclocks nearing 5 ghz no problem. im kinda bummed about the crossfire thing. but i think ill be ok

 

[sunnk]

if u wanna crossfire an card from hd 6900 series then cf the hd 6950 it will be cheaper and deeper in performance .

 

[TheRawkstar]

I was mostly hoping to jst be able to have my 6970 and if i ever needed to upgrade just drop a 6770 or something in there to help out, nothing too extreme. but since i cant do that ill just stick with the 6970, and wait until i need a slightly more extreme upgrade and get another one for cf.

 

[sunnk]

yes a single hd 6970 will be also ok and can max out all games on 50+ fps without aa or with some aa.

 

[de5_Roy]

this is an fx build that uses crossfire.
http://www.tomshardware.com/reviews/fx-overclock-crossfire-ssd,3098.html
another thing: to crossfire, you must use two gfx cards from the same number series e.g. 69xx or 68xx. you can cfx a 6950 with a 6970 but not with a 6850. only exception afaik is 5770 and 6770 cfx - because they are the same cards with some tweaks.

 

[TheRawkstar]

well then I guess ill drop a 6950 in there when i want to upgrade, it will be much cheaper for a similar increase. I heard I can flash the bios on a 6950 and make it run almost exactly as well as a 6970. I guess we will see

 

[Pherule]

An i5 2500K at 4.7Ghz would destroy a Bulldozer at 5Ghz. You really, really want to go with Intel on this one.

Also, why not go for the 7970? If the price is too high, wait a couple of weeks and get the 7950.

 

[refillable]

Well, there is no point to crossfire 6970 with 6950, either get a 6950 crossfire when you can't get a 6970 crossfire, or get the 6970 crossfire if you can get it. You may also wait for the 7950 which tomshardware says will be out on 31 January 2012 (Rumor).

 

[simon12]

A 6950 in crossfire with a 6970 will only run like 2 6950s in crossfire so its a bit pointless getting the 6970 in the 1st place. This is the same for all cards 2 will only run like 2 of the lowest cards. And for gaming a stock 2500K will beat an 8 core bulldozer at 5GHz. Bulldozer just doesn't game well.

 

[saratj1]

You can only crossfire a 6970 with another 6970 or 6950. Crossfire with a 6770 will not work

 

[TheRawkstar]

I don't see the 8 core bulldozer getting destroyed by anything, 8 cores at 5 ghz is 40 ghz of processing all in 8 literal cores. I understand via hyperthreading intel's i5's and i7's register as 8 cores in your device manager and have fantastic performance. but the entire purpose of this build is to make a system to test amd's scorpius platform (my roommate is also building a desktop, he is using intel and we plan on comparing and sharing our results) and for the price (under $1000) I'm going to be getting some very impressive framerates. Also I wasnt going with the 7000 series yet because I havent had a chance to check if it is also compatible with the platform, or how much more expensive it is versus the 6000 series

 

[simon12]

At 4.5GHz it only just beats a stock Phenom x4 980 and can't beat a stock 2600K or a overclcoked phenom x6

 

[refillable]

The price of 7950 should be $350-$400 I think and 'should' have the performance better or same as 6970 with the power consumption like 6950. This is an opinion though. Good luck on comparing your Scorpius system with your friend's sandy bridge.

And just to tell you, you need a really good cooling and good voltage tune up to go 5Ghz with FX-8120. Cooler should be something like this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16835103056

Also, your system is going to be really power Hungry when overclocked at 5Ghz with 6970 Crossfire, You need to AT LEAST get something like this to be safe:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817207017

 

[TheRawkstar]

well i guess the only thing i need to figure out is if this scorpius platform provides a decent enough bonus to make an 8120 worth it over an i5 2500k

 

[simon12]

For gaming the 2500K every time without the overclock the dual core i3 2100 would beat the FX 8150.

 

[sunnk]

before buying any graphic card look at this the details of hd 7950 and 7990 has been leaked http://www.tomshardware.com/news/AMD-Radeon-HD7990-HD7950-ati,14366.html the price of the hd 7950 will be around $400 or lower according to the information the release of hd 7950 and 7990 will be on 31st jan 2012.

 

[Pherule]

I don't see the 8 core bulldozer getting destroyed by anything

I actually laughed pretty hard at this. Can't tell whether you're trolling, a diehard AMD fan, or simply several years out of whack, so I'll choose to believe the latter and that you don't really know what's going on in the current CPU scene. So I'll inform...

Most current games use 2 cores at most. Some use 4. I haven't heard of any that use 8 cores. With Intel and AMD now you're comparing apples and oranges. Yes I agree that HT sucks. It's good for some applications, but I won't be going with HT again. That doesn't nullify the fact that, with or without HT, a quad core Sandy Bridge machine will outstrip an 8-core Bulldozer in more than 90% of tasks. If you're gaming, Intel is the best route atm.

That doesn't mean the Bulldozer is weak. Oh no, it's a very powerful CPU, but tbh, the Sandy Bridge CPU's are overpowered. If you want to future proof (to some extent), then it's very nice to have something that is overpowered now.

Of course you'll buy the Bulldozer anyway, since you're planning on testing it; nothing wrong with that - I'm merely pointing out that SB is faster.

 

[refillable]

SB is faster at games, but not at Cinebench, MediaShow Espresso, Handbrake and games that are well in 8-core, or benchmark like 3dMark11 (Maybe, because benchmark tend to be programmed better than games). But in games like WoW, Starcraft, Civillization 5, or low resolution, etc. This processor is a joke. It only gives 60-80fps and the SB like more than hundred. No trolls or fanboyism

 

[simon12]

I don't think bulldozer can beat an i5 even in games that can use 8 cores for example the dirt 2 bench I posted above the 1100T beats the 980 more cores at lower speed suggesting it uses at least 6 cores, but the FX without an overclock is beaten by the 4 core 980 @3.7GHz and the 1100T 6 cores @ 3.3GHz. Even with an overclock it can't beat an overclocked 1100T. Remember the 2500K can overclock to 4.5GHz+

 

[refillable]

In fact Mr simon12, I don't believe that benchmark. How can a Phenom II 980 beat an intel 2500k? Remember both X4 980 and i5 2500k is a true quad core and it is not eight. But how can X4 980 beat 2500k? It's not on my mind...

 

[simon12]

In fact Mr simon12, I don't believe that benchmark. How can a Phenom II 980 beat an intel 2500k? Remember both X4 980 and i5 2500k is a true quad core and it is not eight. But how can X4 980 beat 2500k? It's not on my mind...

It is strange but when you look at toms review of that game it did favour AMD CPUs although it was coparing it to 1st generation sandy bridge a 2GHz Phenom x4 beat a 3GHz i7

from http://www.tomshardware.com/reviews/dirt-2-performance-benchmark,2508-10.html

 

[refillable]

Well OP should buy X4 980 then... Am I right?

 

[TheRawkstar]

thanks for all your helpful tips guys! I didnt realize that most programming wouldn't be able to run with all 8 cores i was just running based off of all the impressive numbers amd was throwing at me apparently the i5 2500k is the way to go, but now im wondering if should keep my radeon 6970 gpu, or go with the nvidia gtx 570. both are impressive cards and have similar price points, which one do you feel would perform better with the i5?