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FD76
10-18-04, 05:54 PM
Can it be done? Do you clock each card seperate? Coolbits work at all? Just curious. I guess if nothing else you could just mod the bios's of the cards, huh?

Kojiro
10-19-04, 12:02 AM
I think that both cards would have to be the same clock speed, so if you wer OCing with Coolbits, then the clockspeed will be applied to both cards, at least that is my theory.

K007
10-19-04, 12:16 AM
It has to be..thats why u dont see 6600Gt + 6800GT

Lezmaka
10-19-04, 12:18 AM
It has to be..thats why u dont see 6600Gt + 6800GT

Clockspeed would the least of your problems if you tried that combination.

jAkUp
10-19-04, 12:33 AM
I just wanna know what kinda powersupply can power 2 6800 ultras...

-=DVS=-
10-19-04, 12:38 AM
I just wanna know what kinda powersupply can power 2 6800 ultras...

Im sure server PSU 700W and 45A on 12v line should do just fine :D ZIPPY/EMACS 700W (http://www.newegg.com/app/ViewProductDesc.asp?description=17-103-714&depa=1)

Actually i just read at [H] forum that PCP&C will release 800W+ PSUs soon :eek: A bit crazy that monster will cost ~400$ :eek:

Whilst speaking to sales at PCP&C earlier today they let it be known that they're soon to release 2 new high-end PSUs.


The first, to be known as the Turbo-Cool 850 ETX is due in mid-November.
It's an 850W power supply (rated in PCP&C's standard way) primarily for powering dual CPU + dual GPU systems.
It features 2x 6pin cables for use with PCI Express graphics cards (both in single/dual/SLI configuration).
Also, rather than 2x 4pin power cables, 1x 8pin will be used instead.
Price will be around US$400.


Next is the Turbo-Cool 700 ETX due around Q1 2005.
This is the 700W variant of the above PSU though intended for single CPU setups (only 1x 4pin power cable rather than 2).
2x 6pin cables are featured (in anticipation for SLI'd configurations).
Price should be between the Turbo Cool 510 range and the Turbo-Cool 850 ETX so approx. US$300.


Both supplies take on a new form factor ('ETX' for extended) as although they feature standard ATX height and width, the depth has grown from 5.5" to 9" (from the rear fan grille to where the cables exit the PSU).
Weight has also increased, now coming in at 11lbs.
Efficiency is up-rated to ~85% through the use of even higher quality components than used in the 510 range.
I forgot to confirm but I assume that both supplies feature 24pin plugs as standard (rather than 20pin).
Linky (http://www.hardforum.com/showthread.php?t=814737)

jAkUp
10-19-04, 12:51 AM
Nice!!! Thanks for the info!!

ChrisRay
10-19-04, 12:52 AM
Im sure server PSU 700W and 45A on 12v line should do just fine :D ZIPPY/EMACS 700W (http://www.newegg.com/app/ViewProductDesc.asp?description=17-103-714&depa=1)

Actually i just read at [H] forum that PCP&C will release 800W+ PSUs soon :eek: A bit crazy that monster will cost ~400$ :eek:

[/size]
Linky (http://www.hardforum.com/showthread.php?t=814737)


God. As if I dont suck enough power into my room.. Yikes. 2 PCS with 400 + watt PSU,, and 2 monitors.. imagine adding these monsters in there. Probably blow a circuit.

RealLifePixelShader
10-19-04, 01:30 AM
Good Day

I would like to know what motherboard you guys use for the SLI I cant find any 2 x PCX 16 bus MOBOs anyware

jAkUp
10-19-04, 01:31 AM
There are none yet... in a few days the Nforce4 should be launched which will have the capabilities

Lezmaka
10-19-04, 02:09 AM
There are none yet... in a few days the Nforce4 should be launched which will have the capabilities

If you believe what the Inq says, the nForce4 SLI will be launched/announced a couple weeks later than nForce4 and nForce4 Ultra.

And a quality 600 watt power supply should be just fine, although it'd probably cost over $300. According to xbitlabs (http://www.xbitlabs.com/misc/picture/?src=/images/video/ati-vs-nv-power/6800u_table-b.gif&1=1), a 6800 Ultra uses less than 5 amps off the 12v rail. I built/configured some workstations a little while ago with dual 3.6 Xeon Nocona (basically same core as Prescott) and a QuadroFX 3400 (PCI-E NV40GL), 4GB PC2-400 ram, 3 SCSI hard drives (don't remember if they were 10K or 15K RPM) and a DVD burner. The systems had "only" a 600 watt power supply and the setup had been tested before the order was placed because they wouldn't put up with any kind of problems at all. So, just replace one of those Xeons with another 6800 Ultra and you'd be fine.

FD76
10-19-04, 11:16 AM
HIJACKERS!!.. lol

what i was basically asking.. is does anyone now for sure that you will be able to clock sli... meaning will the driver control all aspects of the two cards as one? or riva tuner or whateva..

55illinois
10-19-04, 11:50 AM
No one knows yet, because no one (at least anyone not under NDA) has even used these things. All this is just specualtion.

Zetto
10-19-04, 03:22 PM
nforce 4 has been announced already... mobos will be available in 30 days :D at a premium of course ;) (read - price gauging :nanahump: )

Unfortunately, no 2x 16 PCIe mobos in near future.. Nforce4 supports only 2x 8 pci-e :D

kahloq
10-19-04, 09:35 PM
HIJACKERS!!.. lol

what i was basically asking.. is does anyone now for sure that you will be able to clock sli... meaning will the driver control all aspects of the two cards as one? or riva tuner or whateva..

Why don'y you email nvidia and ask them

Zetto
10-19-04, 10:03 PM
Why don'y you email nvidia and ask them

NOOOOOO, just buy 2 6800ultras or gts and try it out urself... dont forget to let us know :D

Blacklash
10-21-04, 07:10 AM
http://www.pantherproducts.co.uk/Articles/Graphics/SLI.shtml

"Overclocking
Overclocking the Multi-GPU configuration is possible. However It's unlikely that you will be able to overclock one card more than another. So if one of your Geforce 6800 cards is not a good overclocker than you will be stuck at core speeds. The driver will be able to do this overclocking and will overclock both cards equally for you when you overclock the first."


It should work fine. Ideally you will get two of the same brand cards, like two EVGA 6600 GT's and pray :D You will be limited to the lowest OC on any given card. They must match frequencies.

noko
10-21-04, 09:07 AM
Who whould need to overclock? I know, I probably do it. Still the power of two ultras as in 3d performance will be uterly amazing and I wonder if any cpu combination would even be enough to take advantage of it. I guess those with very high end montors could start to push the combo but the games out today will be nothing for it. If a 600w powersupply is adequate I wonder if my trusty Antec 550w could handle the load?

FD76
10-21-04, 09:34 AM
Thx Malficar.. thats what i was looking for. And Noko.. i was more concerned about being able to clock the almighty GT to save money on the ultra's.. =)

noko
10-21-04, 09:39 AM
Thats true, me too. Still Nvidia has put out something pretty excitting for us to dream about and plan for lol. :D

majortom
10-21-04, 09:41 AM
does anybody have an sli setup in this forum?

Blacklash
10-21-04, 10:00 AM
Thx Malficar.. thats what i was looking for. And Noko.. i was more concerned about being able to clock the almighty GT to save money on the ultra's.. =)

NP. Overclocking two 6600 GT's would be good too. I am seeing some of them peg 560 on the core with regularity in reviews.

kazafa
10-21-04, 11:46 AM
NP. Overclocking two 6600 GT's would be good too. I am seeing some of them peg 560 on the core with regularity in reviews.
6600GT SLI is good idea