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Thread ID: 134705	2013-07-30 22:24:00	PCI-E bandwidth?	Nerdtastic (16693)	Press F1

Post ID	Timestamp	Content	User
1350198	2013-07-30 22:24:00	Hi, I have just got a new motherboard and it has one PCI-E slot running at x16 and another running at x4. (plus I think 2 x1 slots) I have also just got a new Radeon 7850. SO, my question is, if I want to add a second 7850 in crossfire, will it impact performance because the second slot is running at x4? Thanks, Nerdtastic	Nerdtastic (16693)
1350199	2013-07-30 22:31:00	x4 will be quite slow, you would want atleast x8 / x8	Slankydudl (16687)
1350200	2013-07-30 22:33:00	x4 will be quite slow, you would want atleast x8 / x8 But how much will it impact performance? And will the x16 slot be forced to run at x4?	Nerdtastic (16693)
1350201	2013-07-30 22:53:00	The x16 slot will run at either x16 or x8 (def not x4), check the specs for your mobo. The x4 slot would bottleneck you in *some* games, particularly at higher resolutions. It's not ideal but not a total waste of time either. At a rough estimate I'd say you'd lose around 10 - 20% performance compared to full x16/x16 on average.	pablo d (15490)
1350202	2013-07-30 23:14:00	www.gigabyte.com Checking my specs the x16 slot runs at x4 when CrossfireX is enabled? Will this make a big difference and what is the difference between Crossfire and CrossfireX? BTW: How can this be a 'Crossfire' rated motherboard if it so badly hinders performance?	Nerdtastic (16693)
1350203	2013-07-30 23:26:00	I wouldn't bother with Crossfire on a board without dual x8 slots, really, unless you're doing tasks that require significant GPU power but minimal graphics memory throughput (which are particularly niche tasks). It's a Crossfire-capable board because you can make Crossfire work. Doesn't mean it's a good idea.	inphinity (7274)
1350204	2013-07-30 23:44:00	Alot of boards are rated as crossfire compatable but should never actuly be used. It will probably hinder preformance to the point where it really wouldnt be worth the money of a new graphic card. However if you play a lot of physics based games you could get a cheap nvidia card and use that for physx whilst running your 7850. There are a bunch ofways this can be acheived and is worth researching. Although you wont get much load taken off your 7850 as i believe with an amd GPU most physics processing is done by the CPU.	Slankydudl (16687)
1350205	2013-07-30 23:45:00	www.gigabyte.com Checking my specs the x16 slot runs at x4 when CrossfireX is enabled? Will this make a big difference and what is the difference between Crossfire and CrossfireX? BTW: How can this be a 'Crossfire' rated motherboard if it so badly hinders performance? Woah! That's garbage. I have that board and I didn't even know the first slot ran in x4 in Crossfire :p Sorry about the misleading information. You are better off going for a single, better card like a 7970 instead (which is usually a better idea anyway).	pablo d (15490)
1350206	2013-07-31 00:58:00	Woah! That's garbage. I have that board and I didn't even know the first slot ran in x4 in Crossfire :p Sorry about the misleading information. You are better off going for a single, better card like a 7970 instead (which is usually a better idea anyway). My budget restricts what I can buy. I was looking for the future as instead of replacing the card I would just add a second card in Crossfire.	Nerdtastic (16693)
1350207	2013-07-31 01:01:00	My budget restricts what I can buy. I was looking for the future as instead of replacing the card I would just add a second card in Crossfire. Selling your 7850 and adding that to your budget to get a better card would work out about the same as spending $300 on another 7850.	pablo d (15490)
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