My motherboard supports only one slot for 16x, and of course it is the bottom one right next to the PSU and the PCI slots (where a wireless card will be going). Running it in the top one cause it to run at PCIE 8x. Is this a big performance hit in my system? The temps don't seem to be very different in each slot, but I felt more comfortable with it in the top slot.
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Running GTX 470 at 8x or 16x
- Thread starter RoGuE1230
- Start date
Is the motherboard you are talking about the ASUS M4A89GTD Pro/USB3? There's some oddness about this motherboard's PCI-E slots, which I will quote from newegg user reviews:
"Bottom pci-e slot is 16x when using single graphics card. Top slot must have a vga switch card inserted into it in order for the bottom slot to run at 16x on a single graphics card. If the switch card isn't inserted, then the bottom slot will run at 8x." I'm not sure, but from other reading, I'm not sure it works if you put the vga switch in the bottom slot. The expansion slot layout was widely considered to be pretty bad on this motherboard so you may have no choice but to run at 8x.
That being said, this is a PCI-E 2.0 motherboard, so 8x would be equivalent to 16x PCI-E 1.x. There should be no performance hit with a single video card.
"Bottom pci-e slot is 16x when using single graphics card. Top slot must have a vga switch card inserted into it in order for the bottom slot to run at 16x on a single graphics card. If the switch card isn't inserted, then the bottom slot will run at 8x." I'm not sure, but from other reading, I'm not sure it works if you put the vga switch in the bottom slot. The expansion slot layout was widely considered to be pretty bad on this motherboard so you may have no choice but to run at 8x.
That being said, this is a PCI-E 2.0 motherboard, so 8x would be equivalent to 16x PCI-E 1.x. There should be no performance hit with a single video card.
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Yeah, this one is a little odd. The VGA switch card/Video card only works in one direction, otherwise all you get is no signal to the montior. Ask me how I know. lol
But if there shouldn't be any performance hit with a single video card, I think I'll just leave it at 8x in the top slot.
But if there shouldn't be any performance hit with a single video card, I think I'll just leave it at 8x in the top slot.
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Fantasyalive
Limp Gawd
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- Nov 3, 2010
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I have an AMD Biostar 790 that does the same thing. Only it won't even recognize the video card in the top slot with nothing in the bottom =/. Installing this mobo was my first mobo installation and I didn't read that it had to be in the bottom slot to work so when it wouldn't start up I was afraid that I had somehow burnt my brand new mobo. Was really glad though when my friend told me wrong slot 