Advice with 8800 GTS (G92)

[Wibbly]

I'm wondering with a PSU that has 2 or more 12v rails, what the amperage requirement on those rails should be. I've read that the amperage requirement for one of these cards is 26A minimum, but my PSU has two 20A rails.

Some games, give me strange artifacts, and others work totally without issue. Underclocking the card makes no difference whatsoever. I don't want to RMA the card only to find out it's fine, and the PSU is to blame, and likewise I don't want to shell out on a new PSU, only to have to RMA the card still. Sadly, I don't have a single rail PSU with more than 26A on it, the other machine has a single rail rated at 25A (and the exact same things happen with that).

I'm running it on the following system:

Gigabyte GA-P35-S3G (BIOS F2)
Intel Core 2 Duo E7200 (Wolfdale)
2x1Gb Geil PC2-6400 (GX22GB6400DC)
MSI NX8800GTS 512 OC (T2D512E)
SoundBlaster Audigy 2 ZS
Maxtor 6Y120P0 120Gb IDE HD
WDC WD2500Js-60NCB1 Sata 2 HD
Rosewill 16x IDE DVD Burner

HIPPRO TOP500-P5 500Watt PSU:
+3.3V - 28A
+5V - 44A
+12V1 - 20A
+12V2 - 20A
-12V - 1A
-5V - 0.8A
+5Vsb - 2.5A

Have tried my old 7950GT on it, and all works fine, and then stuck the 8800GTS onto the old system which is:

EPoX 9NPA3 Ultra
AMD 64 3700+ San Diego
2x1Gb G-Skill DDR400
(normally the XFX 7950GT Extreme)
2xWDC 160Gb IDE HD
Sony 16x IDE DVD player
Brand new Logisys PS575XBX PSU: +3.3V-38A +5V-40A +12V-25A -5V-0.5A -12V-0.8A +5VSB-2A


The artifacts never happen on scenery, it's only people/creature models, and depending on your angle toward a light source, goes from virtually nothing to absolutely huge flickering polys. Affected games I have are The Witcher (and only seen it on the female character in the cutscenes, doesn't ssem to appear anywhere else yet, haven't played it much though) Lost Planet, UT3 and the Requiem Bloodymare openbeta.
Before the game starts in UT, no problems are seen as you run around the map, but as soon as you are in game proper, they appear to bounce off some of the weapons. The spinning weapons on the floor are fine, only the one you are holding does it. The link gun doesn't even do it.
On my son's system (the second mentioned set of specs) he has a game called Lineage 2, and that works fine with all the settings, except the one labelled "improved shader effect". The HDR and stuff all works, only switching on the improved shader effect causes it (and not on the water or anything else, just bouncing off player and npc models). Don't know if that helps narrow it down.

Games like COD4, GRID, Battlefield 2 and 2142, Live for speed, GTR2, GTL all work fine without issue. It's odd, because I can play any of these for hours on end, and not one hiccup. Even on the games that mess up, I can play them for hours and hours no problem, it's just exceptionally ugly at times, and more than a little offputting.

Hopefully someone has seen this kind of behaviour before, and can tell me whether I need to RMA my card or whether I need to invest in a new PSU.
If it's the latter, I'd REALLY really like to know what specs it should have. I don't want to spend a fortune on a gazillion watt PSU with one rail that has 400billion amps on it, I was looking at an Antec 550 that had 3 rails, 22A, 22A and 25A. Any cheaper alternatives that are known to work with the 8800GTS G92 are welcome. Just some solid specs for how many amps a multi rail PSU should have to be guaranteed to work would be great (provided of course that 2x20A isn't up to the job and is the most likely cause of my trouble).

[Miker]

I have to say, you said that the card is made by MSI, so you need to go to them for support.

"MSI NX8800GTS 512 OC (T2D512E)"'

Put one of the 12v rails from your PSU just to the graphics, no drives or even fans and see if it helps.

[Wibbly]

Yes, I know the card is MSI (my other ones are XFX), but all these nvidia cards have the same power requirements. It seems that no manufacturer actually knows what the requirements are for a 2 or more rail system.
Considering that some while ago ATX specification wished to standardise the use of multiple rails, and the subsequent ensuing of 2 or more 12v rail PSUs, I'm a little confused as to why it's so hard to get such a basic piece of information.

Thanks for taking the time to reply though, as you can imagine, MSI support also failed to provide a specification on dual rail PSUs, and simply said "If the card is faulty, RMA it" which is why I thought I'd try here before actually doing an RMA with them.

Would kind of prefer to have some definite facts about PSU requirement before I send it back knowing it is indeed faulty. I did try only having a single drive hooked up, underclocking the card, stepping the CPU back, using the 2 molex to 6 pin power also, same results every time. Hoped maybe someone here on this forum had seen the same thing before, and could verify either a card or power issue.

If the XFX version hadn't been out of stock when I ordered, I'd have gotten that.

Thanks again anyway.

[mivanx77]

Yes, I know the card is MSI (my other ones are XFX), but all these nvidia cards have the same power requirements. It seems that no manufacturer actually knows what the requirements are for a 2 or more rail system.
Considering that some while ago ATX specification wished to standardise the use of multiple rails, and the subsequent ensuing of 2 or more 12v rail PSUs, I'm a little confused as to why it's so hard to get such a basic piece of information.

Thanks for taking the time to reply though, as you can imagine, MSI support also failed to provide a specification on dual rail PSUs, and simply said "If the card is faulty, RMA it" which is why I thought I'd try here before actually doing an RMA with them.

Would kind of prefer to have some definite facts about PSU requirement before I send it back knowing it is indeed faulty. I did try only having a single drive hooked up, underclocking the card, stepping the CPU back, using the 2 molex to 6 pin power also, same results every time. Hoped maybe someone here on this forum had seen the same thing before, and could verify either a card or power issue.

If the XFX version hadn't been out of stock when I ordered, I'd have gotten that.

Thanks again anyway.
XFXSupport is right, try removing unnecessary parts such as fans hard drives that are not needed for running the OS. Then try playing the games to see if the PSU is giving enough power.

[XFX Tech]

I don't have a list of the exact power requirements in front of me right now but the card is able to run in a PCIE Gen 1 slot so that is 75W and the PCIE 6 pin is 75W. 150W/12V= 12.5A so the card has to pull under 12.5A of 12V power. I would guess that it pulls very close to the maximum though. It leaves you with a little room and those rails can be pulled harder than the 75W on occasion. If you make sure the other devices are on the other 12V rail you shouldn't have any problems as long as the PSU is functioning properly.