Power Requirements


Current generation graphics cards are near the limit for how much current they are allowed to pull from one connection. So, of course, the solution is to add a second power connection to the card. That's right, the GeForce 6800 Ultra requires two independent connections to the power supply. The lines could probably be connected to a fan with no problem, but each line should really be free of any other connection.

Of course, this is a bit of an inconvenience for people who (like the writer of this article) have 4 or more drives connected to their PCs. Power connections are a limited resource in PCs, and this certainly doesn't help. Of course, it might just be worth it. We'll only make you wait a little longer to find out.

The card doesn't necessarily max out both lines (and we are looking into measuring the amperage the cards draw), but, NVIDIA indicated (in the reviewers guide with which we were supplied) that we should use a 480W power supply in conjunction with the 6800 Ultra.

There are a couple factors at work here. First, obviously, the card needs a good amount of power. Second, power supplies generally partition the power they deliver. If you look on the side of a power supply, you'll see a list of voltage rails and amperages. The wattage ratings on a power supply usually indicate (for marketing purposes) the maximum wattage they could supply if the maximum current allowed was drawn on each line. It is not possible to draw all 350 watts of a 350 watt power supply across one connection (or even one rail). NVIDIA indicated that their card needs a stable 12 volt rail, but that generally power supplies offer a large portion of their 12 volt amperage to the motherboard (since the motherboard draws the most power in the system on all rails).

Many people have been worried about heat generated by a card that requires two power connections. Just to be clear, we aren't drawing twice the power because we have twice the connection, nor are we generating twice as much heat. It's a larger chip, it draws more power, but it won't be clocked as high (with the 6800 Ultra version coming in at 400MHz as opposed to the 5950's 475MHz).

Customers who end up buying this card will most likely need to upgrade their power supply as well. Obviously this isn't an optimal solution, and it will turn some people off. But, to those who like the performance numbers, it may be worth the investment. And there are obviously rumors circulating the net about ATI's next generation solution as well, but we will have to wait and see how they tackle the power problem in a few weeks.
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  • Deanz79 - Wednesday, April 14, 2004 - link

    AWESOME!! I wouldnt mind borrowing the card for the night :P
  • TrogdorJW - Wednesday, April 14, 2004 - link

    There are a few things I take away from all the previews of the 6800 Ultra.

    One is that ATI is going to be hard pressed to actually top it. Both will have 16x1 designs, but I don't think ATI will have the 32x0 option, which might be important for games with lots of shadows. (I believe the ATI cards are going to be around 180 million transistors, which leads me to believe that they will not have quite as many features.) I also doubt that ATI will actually support fp32 this time around, which aces DX9.0c/PS3 support from them. That may or may not really matter.

    The next thing is sort of related to the first point: Nvidia now has more features that ATI, but there are still some bugs to work out. DX9 games that were optimized for NV3x seem to be dropping quality on the 6800U. Hopefully the fix to use fp32 instead of fp16 will be both easy and not result in a major performance drop. We'll have to wait and see, though. Other sites have shown quite a few areas that need driver revs, but that's nothing new. At least with NVidia, I feel confident their driver team will fix any major issues and probably increase performance a decent amount as well.

    I also agree with someone else that said the previews might be lower clocked than the final release. First, the RAM is spec'ed for 600 MHz, which makes it odd that they're running at 550 MHz. They may not hit 600, but 575 or maybe 585 seems likely (or at the very least that should be an OC'ing option). The core is currently at 400 MHz, and I think they might be able to bump that up a bit more, but 222 million transistors at .13 micron might not go much higher. We'll have to see what some of the shipping cards from GB, A-bit, Asus, etc. offer in terms of OC'ing headroom, as they might offer better cooling solutions.

    Related to the heat and clockspeed, I'm a little shocked at the heatsink/fan design. If they're going to all the trouble of having a huge HSF, I can't see any reason to not switch the direction it blows and have the Ultra version vent the hot air outside the case. Maybe noise was the reason, or component placement, but I would really prefer to have anything that size making use of external venting. It would be like having your power supply sucking air into the case instead of blowing out... Sure, it might cool the PS better, but the case temp would jump dramatically.

    My final thought is that it will be very interesting to see what sort of price and performance can be had from the regular 6800 cards, and even the 6800XT. I didn't think there would be a "soft-mod" option for Nvidia this round, but it appears I was wrong. Unless NVidia has some way of preventing this from being done. Regardless, if the 6800U is going to start at $500 and the 6800 will go for $300, we could be looking at a 6800XT for $200 or so. It should also have at least the performance of the 5950U, and most likely better.

    Incidentally, I'm betting the mid-range cards (i.e. 6500 or 6600 or whatever) will not really be that great, though, as they'll likely trim them down to 2 or 4 vertex pipelines and 4 or 8 pixel pipelines, so they'll end up looking like something inbetween the 5700U and the 5900XT. And don't look for help from ATI here, as the X300 and X600 look to be renamed 9600SE and 9600XT parts, respectively (a la the Radeon 9000 to 9200 line).
  • IamTHEsnake - Wednesday, April 14, 2004 - link

    Whoops! The Radeon 9800 xt only scored 6138 while NV40 scored 12350+ in 3DMark'03. That Ladies and Gentlemen is 2x as many points!
  • IamTHEsnake - Wednesday, April 14, 2004 - link

    Wow I read the review and all I can say is WoW. I read somewhere else that this card scored 12250+ in 3dMark'03 while the 9800 xt scored 8350 on the same system, same set-up. From one generation to the next 33% increase is not bad. not bad at all.


    Come on ATi! I'm rootin' for you!!!
  • Schadenfroh - Wednesday, April 14, 2004 - link

    what mobo and mobo drivers were used? i hear that the nforce2 provides an unfair performance advantage for nvidia, even tho the ati should run at the same speed as on a differant motherboard, nvidia just gets an extra boost
  • Warder45 - Wednesday, April 14, 2004 - link

    I want to see the multimedia bench's. Hopefully another article with AMD vs Intel.
  • AlexWade - Wednesday, April 14, 2004 - link

    The thing is freakin' huge! I'm willing to bet dollars-to-doughnuts that ATI's new card isn't the size of a football. Even if this huge beast tops in performance, the extra 20 pounds rules out LAN parties.

    I'll admit, the performance is great. But if ATI is smaller and performs near, or slightly below, then that is the one to buy.
  • AlexWade - Wednesday, April 14, 2004 - link

    The thing is freakin' huge! I'm willing to bet dollars-to-doughnuts that ATI's new card isn't the size of a football. Even if this huge beast tops in performance, the extra 20 pounds rules out LAN parties.

    I'll admit, the performance is great. But if ATI is smaller and performs near, or slightly below, then that is the one to buy.
  • Reflex - Wednesday, April 14, 2004 - link

    Personally I'll wait to see the budget line on these, I refuse to spend more than $200 on a video card. Chances are I'll end up going Ati however, the 2D video quality is just noticably better, and most of my time on my PC is spent reading, not gaming.

    Oh well, at least the gamers can be happy again. Too bad the AGP slot is not at the bottom of the motherboard, could build some interesting external vented cases if the card could stick that fan outside the case. ;)
  • Reliant - Wednesday, April 14, 2004 - link

    Any ideas how the Non Ultra version will perform?

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