GTX465 SLI on HP Z800
 

Hi guys,

I'm new here and I'm having a problem getting SLI enabled on my Z800. I have 2 GTX465 cards and they are recognized by the computer, however, when I boot up and open the nvidia control panel the option to enable SLI is not available. The SLI bridge is installed.

Is there anything special I need to do to get SLI working? I've tried removing and reinstalling the drivers and nvidia software and it didn't seem to help.

Thanks!

Are the cards placed in PCIe x16 x16 or at least in x16 x8?

Are they "matching" cards. I know another user on another forum had issues getting SLI going on 2 580's with different RAM amounts(1.5 and 3GB) He ended up having to use this to get his SLI working.
Not saying that is the problem but need a little more info.

What chipset does that board us?

I find the Z800 on the HP site, but it lists it as a workstation setup. If it has a higher end Intel chipset, then that maybe why SLI is not working.

Yes, the cards are placed in the two PCIe x16 slots. For the most part they are matching - the cards are from different manufacturers but they have the same RAM amount (and from what I've read on the nvidia SLI FAQ site, running different manufacturers of the same model should be okay...). The Z800 uses the Intel 5520 chipset.

I know this computer supports SLI because they've been advertising this machine running quadros in SLI, so I would think running a pair of geforces in SLI shouldn't be a problem...

Just because it can run Quadros in SLI doesn't mean that the driver will support GeForce cards running in SLI. The driver does a check with the bios to see if the board manufacturer paid the SLI premium.

I don't know if it differentiates from Quadro to Geforce cards though.

are you talking the nvidia driver or a chipset driver?

The nVidia driver looks to make sure the board is on the approved SLI list. If it is not, then SLI is not allowed. There is some check that is added in the BIOS and that is what the driver checks for.

Like I said, HP may have paid for SLI on Quadro cards, but that doesn't mean that the same fee pays for Geforce cards. Though that is just speculation on my part.

Your best bet would be to contact HP and ask them is SLI with GeFroce cards are supported on this system.

The 5520 doesn't support SLi with desktop card.

You can try it with HyperSLI, but I'm not sure if HyperSLI is still working, I haven't been keeping up on it lately.

a while ago i saw a thread not in english showing hp z800 with two msi gpus in sli but i can't seem to find the link but i have found this on ebay the guy showing gtx590 in sli not sure maybe he is showing how the hp z800 can fit long gpus anyways here is the link
http://www.ebay.com/itm/CUSTOM-HP-Z8...t_12129wt_1026

Check the SLI bridge? When I upgraded boards I had to use my old bridge because the one I got with the new board wouldn't work. Dunno why, brand new. Maybe it got fried or is a defective part. Not sure if its a common issue or not with the bridges.