pci-express question

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pci-express question (RAID controller)

I bought a 3ware 12 port raid controller (9650SE-12ML). The manual for the raid controller says that it fits in a pci-e x8 and x16 slots. I thought my asus a8n sli premium mobo was going to be fine coz the manual said the pci-e x4 slot supported x8 cards... however when i tried to slot it in, i found the connector on the 3ware card was too big for the x4 slot (silly me). I have a 7900gtx in my blue pci-e x16 slot. The mobo is Sli so i have a spare pci-e x16 slot (black). So my question is, is it ok to use this spare x16 slot, or is this JUST for graphics cards in Sli?

I think i have found a section in my manual which suggests that it is ok to have a graphics card in the pci-e x16 blue slot, and a raid controller in the spare pci-e x16 black slot. But i just wanted to check because the connector on the 3ware raid controller is smaller than the spare pci-e x16 slot.

Thanks
 
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Nope both are seperate, they connect cards using a SLI bridge although it can be done without and loss some perfomance, you can stick whatever you like in there like a Physix card or your card.
 
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ok thanks. So basically with all pci-e x16 slots, u can plug in pci-e x1 x2 x4 x8 and x16 cards that have smaller connectors than the pci-e x16 slot itself?
 
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:) Not 100% without google but I mean you do not need to use the GPU slots for a GPU, they really are not GPU slots but PCI-E 16x slots for any device.
 
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Humate said:
ok thanks. So basically with all pci-e x16 slots, u can plug in pci-e x1 x2 x4 x8 and x16 cards that have smaller connectors than the pci-e x16 slot itself?
Yes, you can plug any PCIe device into a slot with more lanes than the card. If you have an open ended slot (pretty rare mind) you can plug a card with more lanes than the slot and it should still work albeit only over as many lanes (and hence bandwidth limited) as the slot.

For example, I've run my RocketRAID 2320 (PCIe 4x) in a PCIe 16x slot before with no problems.
 
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Can you please keep us updated on this, since I am in this same boat as you.

I am waiting for my motherboard so that I can start playing with my new PCI-Express x8 SAS controller.
 
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I plugged it into the spare pci-e x16 slot. I had to enable dual video card option in the mobo bios for the card to even be recognised. However, I have a strange problem. I tried turning my pc off and on like 20 times in a row and for some reason the 3ware card is only ever initialised/recognised EXACTLY every other time i boot up my pc. By initialised/recognised I mean that after the a8n's splash screen at bootup it then displays the option to access the controllers bios by pressing alt+3. I have entered the 3ware raid controllers bios and setup a single 500GB seagate barracuda 7200.10 drive as a single device. On the times when the card initialises, windows will recognise this drive in diskmgmt.msc but i havent bothered formatting it yet.

Does anyone have any clue as to why this controller will only ever be recognised/initialised every other time i boot up? I have tried numerous things but to no avail. I have tried the following already (1) connecting the asus EZ plug (a molex power connector that u are meant to use when using sli graphics cards to even out power or sometihng), (2) disabling the silicon image RAID controller that is on the mobo, (3) disabling quick boot option in the bios (4) updating the asus mobo bios to the latest 009 version (5) updating the firmware on the raid controller.

Im just about all out of ideas. :rolleyes:

One thing i havent tried is swapping the graphics card over into the black second pci-e x16 slot and moving the raid controller over to the first x16 blue slot. But i presume the computer looks for the graphics card in the blue slot first and will have a baby if i swap the cards this way round?
 
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ok... its all working fine now.

Just in case u have any problems Diene i got mine working by turning on dual link graphics in bios and then swapping the graphics card over into the second pci-e x16 slot (which i didnt think would work but does) and moving the RAID controller over into the first pci-e x16 slot. The card is recognised every time now. I also connected the asus EZ plug molex power connector.

Now all i gotta do is get some drives ordered, and tidy up the cables in this computer. WHAT A MESS !

:D
 
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Humate said:
ok... its all working fine now.

Just in case u have any problems Diene i got mine working by turning on dual link graphics in bios and then swapping the graphics card over into the second pci-e x16 slot (which i didnt think would work but does) and moving the RAID controller over into the first pci-e x16 slot. The card is recognised every time now. I also connected the asus EZ plug molex power connector.

Now all i gotta do is get some drives ordered, and tidy up the cables in this computer. WHAT A MESS !

:D

Doesnt that mean that the gfx card is now working at 4x instead of 16x?
 
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im not sure... how can i check?

The manual says that in dual graphics mode each channel drops to x8. So i presume both are now x8.
 
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It depends on your mobo, if the manual says they both are running at 8x, that should be fine then.

Thanks a lot for your help, will keep you updated on my findings once I have all the hardware here.
 
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