How to hook up CrossFire?

[keogh]

Howdy,

Sorry if this is a dumb question, but I have been building PC's for a while, but I have NEVER had 2x of a specific card for Crossfire or SLI, so not sure how it works.

I just bought new components(see below) from ocuk today for a new system and at some point (maybe very soon) I will get a second Sapphire 4870x2 to run in Crossfire, but how do you hook them up? Do I simply plug the second card into the second PCI-E x16 slot below the first, then connect them two cards with one of those bridge connector things, and power it of course... is that all I need to do? Do I get those bridge connectors with the ati cards? Or do I need to buy them seperately?

Spec below incase it matters:

Coolermaster Real Power 850w Modular Power Supply
Asus P5E Intel X38 (Socket 775) PCI-Express DDR2 Motherboard
Western Digital VelociRaptor 150GB 10000RPM SATA-II 16MB Cache - OEM (WD1500HLFS)
Corsair 4GB DDR2 XMS2 Dominator PC2-8500C5 TwinX (2x2GB) Supplied with Airflow Fan (TWIN2X4096-8500C5DF)
Antec P182 Super Midi Tower Case - No PSU (Gun Metal Black)
Samsung SH-S223F/BEBE 22x DVD±RW SATA Dual Layer ReWriter (Black) - OEM
Sapphire ATI Radeon HD 4870 X2 2048MB GDDR5 TV-Out/Dual DVI/HDMI (PCI-Express) - Retail
Intel Core 2 Quad Q9550 LGA775 'Yorkfield' 2.83GHz 12MB-cache (1333FSB) Processor - Retail

Any info would be appreciated!

ta

 

[RichL]

It's just how you describe, then making sure everything is configured correcting in catalyst control centre. You might want to check if your PSU has enough power on the 12V rail too. You'll need good cooling too.

I don't think you will see much benefit from crossfireX 4870X2 tbh, you are relying on a decent scaling profile in the drivers for each game. I think you will only benefit at 2560x1600 with massive amounts of AA and AF. I imagine performance will be quite dependent on your CPU overclock too.

 

[keogh]

It's just how you describe, then making sure everything is configured correcting in catalyst control centre. You might want to check if your PSU has enough power on the 12V rail too. You'll need good cooling too.

I don't think you will see much benefit from crossfireX 4870X2 tbh, you are relying on a decent scaling profile in the drivers for each game. I think you will only benefit at 2560x1600 with massive amounts of AA and AF. I imagine performance will be quite dependent on your CPU overclock too.

Helpful reply, thanks Rich!

The main question really was how to hook it all up (which you answered), I'll cross the other bridges when and if I get a second card.

cheers