ATI 4870 Crossfire help

[jwnorbury]

Hey
With the new ATI Radeon 5XXX series out the price of the ATI 4870 card has droped a lot. I already have a Sapphire ATI Radeon 4870 512MB card, but I really want to put another 4870 in my system and run them together using crossifre.

Can someone tell me if this card would be compatable with my one. I have read in the sticky that the 1GB card will work, but will only run at 512MB. (I am getting the 1GB card because it is the cheapest one I can find)

http://www.lambda-tek.com/componentshop/index.pl?prodID=B209985&viewSpec=y&showold=#productTop

I am also going to upgrade my motherboard from a GIGABYTE GA-EP31 to an Asus P5Q PRO.

http://www.lambda-tek.com/componentshop/index.pl?prodID=C-B127041&viewSpec=y&showold=#productTop

I currently have:

Intel Core2 Quad Q9800
ATI 4870
GA-EP31-DS3L
4GB DDR2

Also any suggestions where to buy second hand graphics cards/motherboards so I can get it for cheaper. Thanks

 

[jwnorbury]

Also I need to keep the total of the card and board bellow £150

 

[metalweenis]

I was also contemplating doing this but I am not so sure now. The performance of these two cards is very good indeed, matching or beating a 5850/5870 depending on the game but the drivers are poorly optimized. Also, you would be jumping on the DX10 wagon with no DX11 support. It shouldn't matter what card you put in there whether it's 1GB or 512MB, though if it were me I'd be looking for the exact 4870 that you have currently.

There's also factors like; PSU size/quality, heat, noise, CPU bottleneck(depending on your CPU), driver stability.

This is what has shyed me away from going this route. And honestly, what game out right now other than Crysis needs more than one 4870?

I guess the decision is up to you.

 

[jwnorbury]

The main reason I wanted to do this was to get more power out my GPU without spending the money to get the 5850 or 5870, the power isn't quite the same. And I do own a copy of all the crysis games, and one of the main reasons I've not been playing them because of the way it ran on one 4870.

I just bought this cpu and have overclocked it to 3.14Ghz, but can get it higher, 6mb 2l cache, so that isn't holding me back, and noice doesn't matter overly for me, I have a good set of speakers and do almost all my games with my headset on so noice doesn't make much of a difference.

I've looked a lot for a card that is identical but can not find one, does the board that I've linked look like it will be able to handle Crossfire and high end gaming?

 

[jwnorbury]

I supose I could wait till the 5870 drops after xmas, and keep my current motherboard and I'd get direct x 11. Seems like there are lots of factors to consider. I was just attracted to the idea by the relative low cost.

 

[metalweenis]

I have the Asus P5Q PRO myself, it shouldn't have any problems running CrossFire. The 5850 is the best option for price/performance currently. The 5870 is overpriced for what you get IMO.

By the way, I am able to run Crysis with my system and the same card.

 

[redgarl]

It should work. 2 4870 is really a strong setup. I got 2 OC 4850 that I bought really cheap abd they are as fast as 2 4870... simply incredible.

 

[Duesouth]

both cards have to be identical for the cross fire to work properly, same card to the specs, manufacture, model, ram. so ati yes hmm lets see, is it a diamond, saphire, eah, and so on. both must be the same manufacture, diamond or sapphire. the ram too. you will have problems if the cards are a diamond and a sapphire. must be identical to both specs. which stop me from doing a crossfire since the release of the 4890, the 4870 where I am at has just evaporated off the shelf and the stores are no longer ordering the ati 4870 1 gig diamond. so I am stuck now since my next upgrade will be another pc from scratch when the time comes because one 4870 is just plenty for me. later. some people say that the same specs to not matter and they do not know what they are talking about. later

 

[metalweenis]

All in all, not worth it.

 

[jwnorbury]

Okay, thanks guys. I think I'll stick with my 4870, I've overclocked it a bit, might be able to push it a little bit more. Then in the post xmas sale I'll get a 5870 or 5890 if they're out yet.

 

[erdinger]

WoW wait a minute since when do both cards need to be from the same manufacturer to run xfire? Have you got any link to prove that?

As far as I know you can even let a 4890 run xfire together with a 4870 (the 4890 will just slow down to the speeds of the 4870)

 

[jwnorbury]

That is true, my friend is doing that at the moment with a 4870 and a 4890. But I still think that I should wait for the 5870. Just because after xmas the price will drop.

 

[jwnorbury]

Also, 5870 will have DX11, where the 4870 will not, and I'm asuming that a 4870X4890 wont either.

 

[PIPELAYER]

Is a single 4870/512 as powerfull as a single 260 nvidia? I have preorderd battlefield bad company 2 and the specs are out today. Im not worried about my pc I got asus maxima formulla 2 and a quad core pros. any help plz. and yes ive wonderd if a 5850 or a 5870 would better than two 4870

 

[hell_storm2004]

^^ By 260 nVidia i think you mean GTX260... The performance of GTX260 is similar to HD4870. HD5850 is a very good value for money card and i think the price would come around HD4870x2.