2 3870's in Xfire or X2?

[erocker]

Help me decide people!:)

[panchoman]

i say grab the x2 ddr4 because:

-less space, power, heat, etc.
-only takes one slot --> ability to expand to quad fire, whereas you might not have a quad x16 board.

[erocker]

X2 DDR4 isn't released yet. I'm making the purchase tonight.

[JrRacinFan]

Hate to say it, 3870x2. For same reasons as above!

EDIT: Even if it isn't DDR4.

[panchoman]

get the x2 even if it isn't the new one..

though i've heard the new one is gddr4 & pci 2.0

[Bytor]

A pair of 3870's..

[erocker]

A pair of 3870's..

Reasons? And keep em coming!:)

[Bytor]

Mainly GDDR4, and they clock up well. I would like to see more bench's on them. Mainly bench's on AMD rigs since thats what I'm using. I would like to see if one X2 runs better than my pair of 3870's. A pair of X2's would be nice, but that would only work in Vista and I have no plan's on moving to vista.

[panchoman]

trying to find some benchies of x2 vs CF

[panchoman]

http://www.hardwarecanucks.com/forum...review-11.html
http://www.hardwarecanucks.com/forum...review-16.html

http://www.anandtech.com/video/showdoc.aspx?i=3209&p=13

[Sh00t1st]

i would say look up reviews of the two cards, in here or in other websites :-p, try to find one with the same motherboard as your using, its what i do when i look for hardware, kinda gives you an idea of what its going to do performance wise.
that being said, the x2 unless you can find 2 3870's for cheaper than the x2, if you can than i would go with that, seeing as its not 2 video cards sharing 1 16x buss like the x2 would be if you bought it, i would think you could net better bandwidth/performance with the 2 3870's seeing as you would have 32 pcie lanes instead of just one 16 lane for the x2.
i might be totaly wrong but its my opinion and i think the logic is somewhat sound who knows tho :). :roll:

[Dr. Spankenstein]

Crossfire two cards.

I'm hard-pressed to explain why, but I am still a little dubious about the X2.

Just like the "luck of the draw" on CPUs, no two chips clock the same. You will be "locked" into the speed of the lesser chip. Althought the arbiter PLX chip seems to do a good job at linking the cards, I like to be able to mix and match.

Again, the downside is two slots (or more) are covered.

Just me though...

[erocker]

I'm leaning towards two HIS 3870's. (yeah, I know about the aluminum, but it works great with the heatpipe) Two of them are cheaper, plus I have a spider platform besides my Maximus that I could throw both of them in plus my 3850! But keep the comments coming, I figure I'll make the purchase in an hour.


*Dr. Spankenstien, if I do get two cards, you'll help me get em workin.. right!?:D

[Sh00t1st]

HIS isn't really a bad brand its just people don't see them as being mainstream i guess, so they tend to shy away from them. me on the other hand, ive owned saphire and HIS, i like them both. and from what ive seen the aluminum doesnt hinder it, and it releaves the stress of weight that the copper coolers put on the cards. you have a link to the site your using hehe, i wana see them :)

[erocker]

HIS isn't really a bad brand its just people don't see them as being mainstream i guess, so they tend to shy away from them. me on the other hand, ive owned saphire and HIS, i like them both. and from what ive seen the aluminum doesnt hinder it, and it releaves the stress of weight that the copper coolers put on the cards. you have a link to the site your using hehe, i wana see them :)

Absolutely!:) http://www.newegg.com/Product/Product.aspx?Item=N82E16814161218

I still own a HIS x1950pro with basically the same cooler. Plus blue really goes nice with my case.:D

[Bytor]

My pair of Vistiontek 3870's clock pretty much the same, but I have found that one card does take a little more clock speed than the other. With that said I can clock each card to the settings that I want at any given time. I have never used a x2, but I do think you clock them both together. If I'm wrong on that please let me know.

I have looked around and was even tempted at buying a x2 just to test with, but what a purchase just to test eh...

[Dr. Spankenstein]

I'm leaning towards two HIS 3870's. (yeah, I know about the aluminum, but it works great with the heatpipe) Two of them are cheaper, plus I have a spider platform besides my Maximus that I could throw both of them in plus my 3850! But keep the comments coming, I figure I'll make the purchase in an hour.


*Dr. Spankenstien, if I do get two cards, you'll help me get em workin.. right!?:D


You KNOW I will! :toast:

You bring up a good point to consider: You have multiple platforms that could utilize single or multi-gpu. For me, it seems more logical (for you) to go with the two card route.

Plus, people that only have one rig and no backup graphics card could benifit from this arrangement also.

[erocker]

Alright 2 HIS 3870's it is!:D

[Dr. Spankenstein]

Methinks you made the right choice!

Another thing, I think you'll have and easier time selling them off when you want to pick up your R700 card!

You are gonna be pretty happy with your results!

BTW, if you need to "make way" for that Phenom, I'll gladly take that E8400 off your hands!

[KainXS]

2 3870's

the HD3870X2 is more like 2 overclocked 3850's on one chip since it uses DDR3 vs the 3870's DDR4.

so the 3870's all the way

[erocker]

Methinks you made the right choice!

Another thing, I think you'll have and easier time selling them off when you want to pick up your R700 card!

You are gonna be pretty happy with your results!

BTW, if you need to "make way" for that Phenom, I'll gladly take that E8400 off your hands!

No, no 2 systems for me! Mabye I can start running Phenom dedicated server for TPU gaming! :D

[freaksavior]

i don't know if you purchased them or not but i would go 2 x 3870's

if one fails you got another, if one x2 fails ya got nothing.

they perform almost the same so i again say 3870's

[Dr. Spankenstein]

That's using the old noodle!!!

I'm pretty sure that is the route he's going.

G/L, man!

[erocker]

I've got 2 HIS HD 3870's on the way!:rockout:

[freaksavior]

i want to see your results in my 3k thread erocker! no exceptions

[panchoman]

congrats on the purchase man!

p.s. might wanna update the solaris link to the new 3.0 thread ;)

[vivanco]

nice purchase, let us know how it goes :)

[erocker]

It'll be interesting to see 2 3870's plus a 3850 on my AMD machine. I should see my B3 Phenom in two to three weeks! I can't wait to use this Asus 790fx board either.. I love the memory coolers! I also picked up 2 gb'z of Transcend "Jetram" (no heatspreaders) just for it. Nice low cas for AMD! Tomorrow, I head over to Best Buy to see if they have any of those Firedog Lian Li cases for my spider (this one I'm modding:D). Oh, and this nice little kit will be cooling the Phenom: XSPC X2O Pro (http://www.frozencpu.com/products/6476/ex-wat-121/XSPC_X2O_Pro_Universal_CPU_Water-Cooling_Kit_Socket_478_603_604_754_775_939_940_AM2 .html?tl=g30c83) Argh, just realized I'm going to need another PSU too!

[Kei]

I agree that you've made the right choice for the following reasons....

1. every review i've ever read shows 2 3870's using LESS power than a single x2
2. if one dies you have a backup so it doesn't hurt nearly as much
3. it's cheaper so far
4. it looks cooler (sry had to say it but you all know it)

I really like the x2 but I think that going with 2 3870's is smarter if you have no need for the x2...meaning you've got the room for more than 2 cards (#1 reason to buy the x2 is you only have room for 2 cards) AND you have more than one x16 slot of course. I think I'm going to go with double 3870's in the very near future as well for the same reasons as much as I like/want the x2 it's just smarter of me to go with the dual cards instead.

K

[trog100]

one advantage with two cards is u can turn one off.. disable crossfire.. i do.. some things actually go worse with C/F enabled than they do without it..

they do for me anyways.. i would miss not being able to turn it off..

trog

[Kei]

another good point I forgot to mention

am I crazy or do i remember hearing something about being able to disable one of the 3870's in the X2 for certain tasks...maybe i'm just crazy though but what's wrong with that :P

K

[wolf]

the HIS models should treat you nicely as well, i still have a 9800 Pro 128mb Ice-Q, back in the day that DHES was brand new and awesome, but i still think its a great design and HIS build a good card, good luck m8!

if your not too happy with the performance crossfired you can also sell one 3870 which is an advantage over the X2, like you say it'll be cheaper, you can disable crossfire if you want, and they seem to use less power. good choice.

and a happy gaming to you. oh btw, i would love a TPU game server!

[Megasty]

I only enable it for the few dx10 games that I know supports CF which are very few. I don't even have it enabled for any dx9 games but the x2 is more that enough for them. It is a weird card that have 2 gpus connected by a 1.1 pci bus so its no surprize that it out-performs the 3870 in games that don't support CF. I commend ATI for that. The x2 is not CF so you can't disable something that isn't there. A single x2 is faster than 2 3870s but that's because the connection between the gpu's is more solid than CF & the x2 is clocked higher than the 3870 BUT the gpus are exactly the same.

[REVHEAD]

Ok here is why 2 cards are better than an X2, I dont know why this wasnt mentioned.

2 x 3870s use what? they each use a 16x pcie 2.0 slot this in theory gives better performance than say a 8x8 Pcie Setup.

What does a 3870 X2 use? it uses one 16x slot for 2 cards, this is were the loss of performance is had, shure it may not be much , but it all adds up at the end of the day, this is why I went the 2 card soloution.

As for two x2 3870 cards = 4 Gpus it is pointless because the weakest link is the CPU, a 4ghz OC Intel Quad still wouldnt be enough to power 4 gpus it is barley enough to power 2gpus, for evey 100mhz I overclock my CPU I gain 10 fps in 3dmarks 06, this tells me that the CPU is bottlenecking bigtime.

Bring on the Fusion Chip and let the death of the CPU begin, CPUs just dont cut it anymore, the faster our cards get the more CPUs fall behind and cant cope with the Data that is required to feed todays modern bandwidth hungry GPUs.

[trog100]

I only enable it for the few dx10 games that I know supports CF which are very few. I don't even have it enabled for any dx9 games but the x2 is more that enough for them. It is a weird card that have 2 gpus connected by a 1.1 pci bus so its no surprize that it out-performs the 3870 in games that don't support CF. I commend ATI for that. The x2 is not CF so you can't disable something that isn't there. A single x2 is faster than 2 3870s but that's because the connection between the gpu's is more solid than CF & the x2 is clocked higher than the 3870 BUT the gpus are exactly the same.

a look thru freaksaviours 2006 thread should point out the 3xxx cards performance differences.. it makes a very good 3xxx series reference thread..

trog

[Megasty]

As for two x2 3870 cards = 4 Gpus it is pointless because the weakest link is the CPU, a 4ghz OC Intel Quad still wouldnt be enough to power 4 gpus it is barley enough to power 2gpus, for evey 100mhz I overclock my CPU I gain 10 fps in 3dmarks 06, this tells me that the CPU is bottlenecking bigtime.

That's basically a 3dmark 06 problem. It was a big mistake that future mark made when they decided to weigh a pc's graphical performance on the cpu. A great benmark that will show you the pure power of your card is 3dmk 2001, but it'll just test the low level shaders. The only thing that the cpu helps in todays games is load times. As for multi-gpu that basically a drivers issue. The cards are really bottlenecked by the games & if they actually support the way its info is being processed.

BTW, I was just generalizing that the gpu chips are the same, which they are, not that the x2 was 2 3870s stuck together which they are plainly not.

[REVHEAD]

That's basically a 3dmark 06 problem. It was a big mistake that future mark made when they decided to weigh a pc's graphical performance on the cpu. A great benmark that will show you the pure power of your card is 3dmk 2001, but it'll just test the low level shaders. .

I am not going off Marks or final scores, I am going off Max obtainable FPS , try it for yourself.
I have seen results across multiple graphics platforms and its the same for ATI as it is Nvidia.

[Wile E]

I would've gone with the X2, personally. Just so I could add another later. But you really couldn't go wrong with either.

[btarunr]

2x 3870 in CF.

Each GPU gets the maximum bandwidth of 16 PCI-E lanes. In the current 3870 X2's, the lane arbiter used is PCI-E 1.1 compliant...implies each GPU gets PCI-E 1.1 x8 which I feel is less bandwidth for a RV670. The X2 has a PCI-E 1.1 interface and so it requires additional power draw, it's 6 + 8 pin input. But the 2x PCI-E 2.0 cards take in one 6 pin connector each. On the flipside, it's more noisy using two cards.

[Megasty]

I am not going off Marks or final scores, I am going off Max obtainable FPS , try it for yourself.
I have seen results across multiple graphics platforms and its the same for ATI as it is Nvidia.

Well thats a different story. I was just going by what you said in your post. But that is only in games that support CF which I can count on one hand :p But thanks to some generous ppl I have 2 3870x2s, 5 3870s, & 3 3850s. I personally found that tri-fire with the 3870x2 & 3870 works best. 2 3870x2s still have buggy drivers so there's almost no gain with them in any game, which is just garbage :mad:

@ btarunr the x2 actually have a 48x pci-e lane switch, 16x of each gpu, then 16x to pci-e interface. AMD said the performance difference between pci-e 1.1 & 2.0 was 1% :twitch: But I'm sure that's partially based on way these 2 RV670 models are set up. We all know by now that 1.1 is capable of a data rate of 8GB/s while 2.0 is capable of 16 GB/s.

[btarunr]

@ btarunr the x2 actually have a 48x pci-e lane switch, 16x of each gpu, then 16x to pci-e interface. AMD said the performance difference between pci-e 1.1 & 2.0 was 1% :twitch: But I'm sure that's partially based on way these 2 RV670 models are set up. We all know by now that 1.1 is capable of a data rate of 8GB/s while 2.0 is capable of 16 GB/s.

Sure it's 48lanes in all, BUT: the card connects to the system using PCI-E 1.1 interface, right? And that's 16 PCI-E 1.1 lanes in all. How many lanes the switch can give out is hardly of any consequence when the switch itself connects to the system bus using 16 PCI-E 1.1 lanes. So ultimately, the GPU's communicate with the system within that bandwidth. Coarsely the bandwidth of 8 PCI-E 1.1 lanes per GPU.

[Megasty]

Sure it's 48lanes in all, BUT: the card connects to the system using PCI-E 1.1 interface, right? And that's 16 PCI-E 1.1 lanes in all. How many lanes the switch can give out is hardly of any consequence when the switch itself connects to the system bus using 16 PCI-E 1.1 lanes. So ultimately, the GPU's communicate with the system within that bandwidth. Coarsely the bandwidth of 8 PCI-E 1.1 lanes per GPU.

And that is exactly the problem. Its ez to figure out the mistake ATI made when it comes to games.

Lets say that a game sends 2 strings of info to the card for processing, A & B. The stupid switch sends A to gpu0 & B to gpu1, then the gpu's send it back to the switch as AB but the game wants it back as A & B so the switch simply converts it back to A & B, but while all that bull is happening you're getting chopped to bits by an alien in Crysis :roll:

[trog100]

I am not going off Marks or final scores, I am going off Max obtainable FPS , try it for yourself.
I have seen results across multiple graphics platforms and its the same for ATI as it is Nvidia.

2006 is simply out of date.. when it first came out a top end grafix card scored about 6000.. down there its pure grafix power being measured.. the cpu part is a seperate test..

they used to bring out a new 3dmak when scores got to 10000.. over that the cpu started to limit the grafix test.. for some reason known only to futuremark they have just let 2006 slide without the update..

once u get more than one card the entire benchmark grafix tests included is now 100% cpu speed limitted.. record 30000 score are more down to the cpu running at nearly six gig than the grafix cards..

as a grafix card bench its now useless at its default setting.. it was never planned this way its just never been updated and has got this way..

at a guess i would say dx10 only and slow vista take up is the reason..

at higher resolutions and settings a gain will be seen without the 6 gig cpu.. its only at low resolutions and super high frame rates the cpu takes over as the bottleneck..

trog

[erocker]

Well guys, I managed to get both cards for under $350!!! $174.99 ea.! Newegg is truly awesome!!!

[trog100]

Well guys, I managed to get both cards for under $350!!! $174.99 ea.! Newegg is truly awesome!!!

as regards cheapo hardware "america" is truely awsome.. i have just ordered a cheapo by UK standards 3780.. £123.. or the equivalent of 246 US dollars..

trog

[noneed4me2]

http://www.newegg.com/product/product.aspx?item=N82E16814102719 This is a good deal IMO simply for the reason that the coolers are single slot so you don't lose any expansion slots, and if your case has good air flow you should be good to go. The HIS are good too especially at that price. I know you already ordered but if you change your mind for any reason at least this is another option. When the X2 becomes fully pci/e 2.0 compliant and GDDR4 is the time to get it I think. When you upgrade later which we all do you can split the cards to go into other systems you may use or sell em seperately.

[btarunr]

And that is exactly the problem. Its ez to figure out the mistake ATI made when it comes to games.

Lets say that a game sends 2 strings of info to the card for processing, A & B. The stupid switch sends A to gpu0 & B to gpu1, then the gpu's send it back to the switch as AB but the game wants it back as A & B so the switch simply converts it back to A & B, but while all that bull is happening you're getting chopped to bits by an alien in Crysis :roll:

That's not how it works. The HD3870 X2 does AFR or Tiling in multi-GPU supportive 3D apps. AFR= Alternate frame rendering is where the complete scene (wire-frame, shading, textures) are carried out by each GPU, just that when rendering frames 1, 2, 3, 4, GPU1 renders 1,3 and GPU2 renders 2,4. So even if there's an insanely high resolution scene and you get say 30 fps out of it, each GPU actually renders 15 frames. That's how the HD3870 X2 (and the 9800 GX2) make high res scenes viewable/playable.

[MKmods]

Story of my life a day late and a dollar short...lol

I like the dual 3870s (more options with coolers, Acceleros rule, and 2 (or more)cards just looks kick ass)
I also have had good luck with the HIS brand. When I had my X800GTO with the IceQ cooler it kicked the other cards butts. Turned out the IceQ cooler cards had faster memory than the others.

And honestly I am no tech guru but it seems the 3870s would be better that the X2s on a PCI EX 16 slot.

[Megasty]

Story of my life a day late and a dollar short...lol

I like the dual 3870s (more options with coolers, Acceleros rule, and 2 (or more)cards just looks kick ass)
I also have had good luck with the HIS brand. When I had my X800GTO with the IceQ cooler it kicked the other cards butts. Turned out the IceQ cooler cards had faster memory than the others.

And honestly I am no tech guru but it seems the 3870s would be better that the X2s on a PCI EX 16 slot.

On paper yes, but in reality only ATI knows. CFx is still a buggy mess anyway. I'll keep on using tri-fire for now in my main rig cuz its beating any other system I can put together.

I had the lousy AB switches on my mind the other day & was just trying to make a joke out of it. There's no way a super-complex card like that would use an 4-bit switch to handle all those floating points, although it would be terribly funny to see the massive bottleneck that ensues.

However, I do have to agree that 2 kickass products are better than one :rockout:

[erocker]

Well, the poll is closed, I've made my decision. Thanks for the help everyone.:toast: