ATI 4890 limited by PCI-E 8x?

[SourceQuench]

Hi again all,

I have a Gigabyte EP45-UD3P and am thinking about an upgrade to my graphics of an ATI 4890. However, this motherboard has two PCI-E slots for graphics cards...but, I bought an Asus Xonar PCI-E soundcard which for the moment can only fit in the second PCI-E slot (since the card is about 8mm too long to fit in either of the 1x slots).

This then means that the first PCI-E slot is reduced to running at 8x.

My question is, would the 4890 be limited in its performance running in this way (i.e. at 8x instead of 16x)?

Sorry for the basic question - I am rather new to this PCI-E business!

Thank you very much for any help you'd like to give.

[nightkhaos]

Are both the card and the motherboard PCIe 2.0 compliant?

[SourceQuench]

As far as I know the motherboard is PCI-E 2.0, although I am not sure about the soundcard.

[nightkhaos]

As far as I know the motherboard is PCI-E 2.0, although I am not sure about the soundcard.

The sound card will work perfectly well on one channel of PCIe 1.X, I mean, is the VGA card PCIe 2.0 complaint?

The bandwidth required to run a VGA card on PCIe 1.X means you need about 14 channels worth of bandwidth, however, most cards only use about 6 channels worth of bandwidth on 2.0. So if your VGA card and your motherboard are PCIe 2.0 compliant, they will be fine on a 8 channel enabled PCIe 2.0 port.

[sammorris]

PCIe2.0 8x is fine. An HD4890 will run fine with that. If it were PCIe1 you would get a bit of a performance issue.

[CAT-THE-FIFTH]

With an overclocked HD4830 I fin there is no performance hit using an 8x PCI-E 1.0 on my 975x based motherboard. With an X2 type card however a PCI-E 2.0 slot is a must from the reviews I have read.

[nightkhaos]

With an overclocked HD4830 I fin there is no performance hit using an 8x PCI-E 1.0 on my 975x based motherboard. With an X2 type card however a PCI-E 2.0 slot is a must from the reviews I have read.

Not a must but a "if you want to get the full performance that you paid for you would be unwise not to get a PCIe 2.0 8x slot."

[sammorris]

I ran a 4870X2 at 8x fine in a PCIe 2.0 board but I certainly wouldn't recommend it in a PCIe 1 board.

[ashikamlani]

There is little to no performance difference using x8 or x16, but a normal PCIe x1 slot should not be used.

[sammorris]

It can't be used by a graphics card, it wouldn't fit.

[PeterStoba]

It can't be used by a graphics card, it wouldn't fit.

It can if it's an open ended slot

[Blaineoliver]

You can drill out the end and then lob in a pci-e x16 card.

[Voxination]

I've seen people buy a PCI-E x1 riser and dremel out the back of it so they don't void their motherboard warranty, and then put a card such as an 8400GS in there purely for PhysX or extra screens.

[shaithis]

Is it the case or drives preventing the Xonar to fit in the 1x slots?

It may be worth trying to re-jig some items if it's the latter.

[nibbler]

what's the motherboard in question??

[sammorris]

I have a Gigabyte EP45-UD3P

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