Question about Crossfire... - Techist - Tech Forum

Go Back   Techist - Tech Forum > Computer Hardware > New Systems | Building and Buying
Click Here to Login
Closed Thread
 
Thread Tools Display Modes
 
Old 07-01-2010, 08:46 PM   #1 (permalink)
Junior Techie
 
LetJimiTakeOver's Avatar
 
Join Date: Jun 2010
Location: Rep. of Ireland
Posts: 62
Default Question about Crossfire...

Just wondering if it's possible to use 2 same model GFX cards in xfx if they're from a different company.

eg. Is it possible to use a Sapphire HD5870 in crossfire with an ASUS HD5870?
__________________

LetJimiTakeOver is offline  
Old 07-01-2010, 08:47 PM   #2 (permalink)
I don't overclock
 
Fat.Clown's Avatar
 
Join Date: Dec 2006
Location: offline
Posts: 3,326
Default Re: Question about Crossfire...

definitely.
__________________

Fat.Clown is offline  
Old 07-01-2010, 08:50 PM   #3 (permalink)
Junior Techie
 
LetJimiTakeOver's Avatar
 
Join Date: Jun 2010
Location: Rep. of Ireland
Posts: 62
Default Re: Question about Crossfire...

Awesome. Thanks for the fast reply!

Actually another quick question, is using 2 HD5870s in Crossfire worth the cost of the 2nd card? I was just looking at some Crysis benchmarks and crossfire 5870s only gave an average of around 7FPS more than a 5870 overclocked...

Here's the link: http://www.overclock3d.net/reviews/g...ries_roundup/4
LetJimiTakeOver is offline  
Old 07-01-2010, 09:00 PM   #4 (permalink)
True Techie
 
Alive.777's Avatar
 
Join Date: Jan 2010
Location: QLD, Australia
Posts: 201
Default Re: Question about Crossfire...

Some games don't fully utillise crossfire and sli so it doesn't nessesarly mean twice the performance.
Alive.777 is offline  
Old 07-01-2010, 09:28 PM   #5 (permalink)
 
Join Date: Nov 2006
Location: Illinois, USA
Posts: 2,363
Default Re: Question about Crossfire...

To be honest even Crysis runs very well on a single 5870, so you won't really notice a difference with a second one. If you use Eyefinity then it will probably make a bigger difference as having 3 monitors rendering at once is actually capable of pushing the 5870 to its limits. I'm using a single 5870 for Eyefinity and it works fine for most games but Crysis doesn't work at full settings very well.

As far as 2 5870's against one overclocked 5870 I say it's a stupid benchmark. If you're going to overclock your 5870 you might as well overclock 2 5870's in crossfire. To really judge the effect of Crossfire you want the same clock speeds on one card vs. two cards.

As far as brand goes, the computer usually doesn't even know what brand the card is. I have a Diamond 5870 but it just shows up as a Radeon HD 5800 series using ATi-provided drivers.
__________________

CalcProgrammer1 is offline  
Old 07-01-2010, 11:03 PM   #6 (permalink)
True Techie
 
Alive.777's Avatar
 
Join Date: Jan 2010
Location: QLD, Australia
Posts: 201
Default Re: Question about Crossfire...

crossfire would be great, iam considering it
Alive.777 is offline  
Old 07-01-2010, 11:12 PM   #7 (permalink)
 
Join Date: Nov 2006
Location: Illinois, USA
Posts: 2,363
Default Re: Question about Crossfire...

The 5870 has 4 slots, at least the normal one does, the Eyefinity 6 edition has 6 slots.

The regular 5870 has 2 DVI ports, one HDMI port, and one DisplayPort port. As the 5870 chip only has 2 hardware DVI/VGA/HDMI signal generator units, you can only use 2 DVI/VGA/HDMI monitors at once. The third monitor absolutely has to be a DisplayPort monitor. Since DisplayPort monitors are rare and expensive, the more common approach is to use an active DisplayPort to VGA or active DisplayPort to Dual-Link DVI adapter. Note that you CANNOT USE PASSIVE ADAPTERS!!!!! This cannot be stressed enough, as most adapters you see (DisplayPort to DVI or HDMI) are passive. The passive adapters make the DisplayPort output DVI signals, but since the 5870 can only generate two DVI signals at once, you'll have to turn off one of the other monitors.

DisplayPort does NOT have a VGA compatibility mode, so any DisplayPort to VGA adapter will be active (this means it has a converter chip in the adapter that takes DisplayPort signals and converts them to VGA, not using a DVI or HDMI compatibility signal). This means that DisplayPort to VGA adapters are a sure-fire option for Eyefinity. The other kind are DisplayPort to Dual-Link DVI, these are typically larger boxes that have a USB connector to get additional power and they cost upwards of $100.

My setup is 3 Dell st2210 monitors (1920x1080), the left and center are hooked with DVI to the two DVI ports and the right monitor is hooked up with a Sapphire brand DisplayPort to VGA adapter. It works perfectly.

Here is the monitors plugged into my 5870:
__________________

CalcProgrammer1 is offline  
Old 07-01-2010, 11:14 PM   #8 (permalink)
Junior Techie
 
LetJimiTakeOver's Avatar
 
Join Date: Jun 2010
Location: Rep. of Ireland
Posts: 62
Default Re: Question about Crossfire...

@ Calc. When you try to run Crysis at max settings is your CPU or GPU overclocked?

Also, I noticed from your sig that you have an Antec 900 case. How does the 5870 fit? And is there room for a 2nd one? I was gonna go for a full tower but if there's room I'll just go with the 900.
LetJimiTakeOver is offline  
Old 07-01-2010, 11:22 PM   #9 (permalink)
 
Join Date: Nov 2006
Location: Illinois, USA
Posts: 2,363
Default Re: Question about Crossfire...

Crysis ran at max settings, 2x AA on my 1680x1050 monitor and looked amazing. However, on my new monitors it lagged at full settings so I turned down some not-so-major features (keeping the resolution high and disabling AA) and it is playable on the Eyefinity setup. I think it could handle a single 1920x1080 monitor with full settings though I haven't tried.

Here are some pictures for reference:

The monitors plugged into the 5870:


The 5870 in the Antec 900:


It's hard to see with the side fan in the way, but there should be room for a second one right under the one in there. If you want two you may be better off with a different motherboard as the Gigabyte UD3R has the PCIe x16 slots close together and the second one will go right up against the first due to the placement of the single PCI slot. The case isn't at fault here.
__________________

CalcProgrammer1 is offline  
Old 07-01-2010, 11:25 PM   #10 (permalink)
Junior Techie
 
Join Date: Jun 2010
Posts: 64
Default Re: Question about Crossfire...

Quote:
Originally Posted by LetJimiTakeOver View Post
@ Calc. When you try to run Crysis at max settings is your CPU or GPU overclocked?

Also, I noticed from your sig that you have an Antec 900 case. How does the 5870 fit? And is there room for a 2nd one? I was gonna go for a full tower but if there's room I'll just go with the 900.
a single 5870 fits what out a problem, thats my current setup, im confident that if I decide to go cross fire in the future I can make it work. but im gonna have to clean up the cables a bit first hehe
__________________

zero4o3 is offline  
Closed Thread

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Crossfire Question Ethan_Kaizer New Systems | Building and Buying 16 10-31-2008 09:44 AM
Crossfire Q (Crysis not working) pullyalater Overclocking and Modding 2 11-21-2007 11:21 AM
Crossfire question... CrazeD Monitors, Printers and Peripherals 9 10-19-2007 01:25 AM
Power Supply Question + Overclocking Question Grievearz New Systems | Building and Buying 21 09-12-2007 12:59 AM
sli or crossfire? MonkeyBusiness New Systems | Building and Buying 0 08-29-2007 08:16 AM



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 07:50 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.