• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

4850/4870 xfire

Simple_Steve

Simple_Steve

Simple_Steve

Associate
Joined
8 Feb 2010
Posts
142
Location
Sheffield, GB
Hey guys, i did some searching, but i couldn't find anything about this as its a pretty old subject im guessing.
Basically looking at setting up my first Xfire set up using a 4870 1GB and a 4850 1GB to back it up. Looking into it i constantly find tales of missery with Xfire even when running the same spec/model card. So what do you think 2 different models with 2 different ram gradings will be like? Im also on the look out for a HD 4870 1Gb if the 4850 turns out to be a lame duck :P
 
Looks like im in the market for 2 4870's then. And wow, modular PSU's *** so quick to fit! If I bought a 4870 1GB and a 4870 512MB what effects would that have on performance? I understand how the MB would utilise the cards if you had them running as two separate cards, but im not entirely sure how Xfire works. Does it do alternate frames or does it do it the half screen method? And if it does it the half screen method are there ways to alter load to suit each card? Problem is im looking at a total budget of £140 excl p+p and im trying to squeeze the best performance out of that small amount of cash.
 
Somebody else posted the same question (2 x 4870's in x-fire) i told him to be careful as 4870's do tend to run a bit toasty and when you have one on top of another can cause problems. I have a Saphire 4870 with a non-reference cooler (kind of vapor-x type) and this idles at around 55 degrees and goes up to around 80 i think while gaming. That is with a single card. Just make sure you get a decent cooler on them and you may be ok.

As for having 1 x 512Mb and 1 x 1Gb i think it will only use 512Mb from each card but then again i could be wrong
 
I'm interested in getting a second 4850 so i can crossfire.

I game only at 1680 x 1050 so a second 4850 should do the business until DX11 becomes more utilised.

What prices do second hand 4850s go for?
 
Go for it! My 3870s run at different speeds, they don't clock to the lower speed (in my case). Watch out for microstutter though since one card will often return frames quicker than the other one.
 
I have the 880W version. It's massive! I don't want to plug it or anything especially on a graphics link, but its very clean power! I don't have it maxed out or anything, but I got my voltmeter out and the fluctuation throught varying loads is minimal and the asus PC probe readings are surprisingly accurate. I did read a review however before buying this that the 880W is actually rated at 850W but maxes out at 880. which to be honest isn't a problem.

Lynx 24, get in touch!!! i also dnt have enough posts to go on the MM :( Its 250 posts you need to reach harryohh, then you need to be set as trusted also.
 
Thanks for looking out for me Jonny, but as I said i only have £140 to play with and that is literally a max budget. Ocuk was the first place I looked, then ****** then hit the bay. I do prefer new items but with this limmited money im willing to pick up second hand performance cards.
Just in case any1 else is in my situation I have done some background work to see which set up is best Xfire or X2
In many of the benchmarks carried out the x2 card doesn't show the same sort of performance as the 4870 Xfire setups but as the res is increased the Xfire setup starts to drop off and the X2 card caries on with the same fps as before. The only thing I can think of is that this is due to the x2 only using 1 PCI-e slot. It doesn't have the same sort of bus transfer rate as the Xfire does using 2 PCI-e. All in all the x2 is offering better high res performance but if your monitor is 22" or less then Xfire is the way forward.
Still haven't found out how Xfire renders the frames yet. If any1 can shed some light on that im interested to know.

Thanks, steve
 
Simple_Steve said:
Thanks for looking out for me Jonny, but as I said i only have £140 to play with and that is literally a max budget. Ocuk was the first place I looked, then ****** then hit the bay. I do prefer new items but with this limmited money im willing to pick up second hand performance cards.
Just in case any1 else is in my situation I have done some background work to see which set up is best Xfire or X2
In many of the benchmarks carried out the x2 card doesn't show the same sort of performance as the 4870 Xfire setups but as the res is increased the Xfire setup starts to drop off and the X2 card caries on with the same fps as before. The only thing I can think of is that this is due to the x2 only using 1 PCI-e slot. It doesn't have the same sort of bus transfer rate as the Xfire does using 2 PCI-e. All in all the x2 is offering better high res performance but if your monitor is 22" or less then Xfire is the way forward.
Still haven't found out how Xfire renders the frames yet. If any1 can shed some light on that im interested to know.

Thanks, steve
Click to expand...

Crossfire simply shares the load between the 2 or 3 cards it has.

So one willl do a fram and the other will do the other.

Thats a quick example
 
Does make sense when you look at the benchmark results, if they rendered each frame in a 50/50 load in a checkboard method then the frames would stay almost the same regardless of the res, but with each individual frame being rendered alternately it still has a drop off when it comes to high res.
 
You must log in or register to reply here.
Back
Top Bottom