Faulty 7800GS?

[skallben]

Hi,
I bought a new Nvidia 7800gs card a couple of days ago and its been working flawlessly with one exception, when I decided to try and overclock it a little just for fun it failed. I tried both with Coolbits and Rivatuner and both tests even failed at stock speeds or below (!) . Now I figured it was a software problem such as my BIOS or so and I decided to swap cards with my brother(he got the exact same card, Inno3D. After swapping I had no problems, he got them instead, problem isolated to the card then apparantly. Other than that they perform exactly the same at stock speeds.

Im confused, does this mean something is broken? What is the cause and effects of this? Anything else besides clocking capabilities gets effected?
If anyone could give some thoughts on this I would be very happy.
Thank you.

[saphalline]

As I talked about in this thread (http://www.pcguide.com/vb/showthread.php?t=46016), OC'ing is a gamble, not a sure-fire way to increase performance. When a vid card or CPU gets sold to you at a certain clock speed, the manufacturer is only guaranteeing that the product will work at that clock speed. OC'ing is basically like saying "I'm going to ignore the speed rating and see what I can really get out this thing!" Well... you can't always get more. I've seen it myself many times. OC'ing is not a guarantee, pure and simple.

A lot people have been "complaining" lately here on the forums about their lack of OC'ing headroom, and I just don't get it. No offense to anyone, but if you think you can buy a cheaper vid card or CPU or whatever and make up the difference in OC'ing, that's just stupid. OC'ing has no expectation whatsoever other than "hey, let's give it a shot!" It's about the fun and danger and bragging rights if it works. It's not about "this vid card should OC more!"

[skallben]

Thanks for the reply Saphalline, I agree to a certain extent to what you said but not 100%, Ill elaborate and try to make my point clearer.

First off I read up quite a lot on these cards before buying one and for instance; there's one brand who sells these cards overclocked out of the box but its in fact the same as Nvidias reference model. At this point pretty much all brands versions of 7800GS are nothing more than Nvidias reference cards with a different sticker on it. Anyways, the failed tests are whats of importance here, not the OCing itself.

Ive scrounged the web for info on the error I get only to get absolutely nothing in return, Ive not found a single person with the same issue. And as I said, me and my brother bought one each of the exact same card from the same vendor and manufacturer. The only difference is that one of the cards fail the stability tests used in the overclocking applications, even at stock speed or lower which is really why Im worried. Spending the amount of cash that I just did on this only to get a product that might fail doesnt really feel right, but then it might be false alarm I dont know really. Ive had no issues with the card other than this, Ive noticed no artifacts and the two cards give the same performance.

Is there a good program for trying video card stability? I dont mean a benchmark here, Im looking for a program designed for testing stability rather than performance.

[mjc]

The only difference is that one of the cards fail the stability tests used in the overclocking applications, even at stock speed or lower which is really why Im worried.

I'd be very tempted to RMA the card on just that...

[saphalline]

My rant was a rant in general, not just at you.

So it's causing problems even at stock speeds? That is odd. But if this only happens with these OC'ing apps, then it could be software-related and not a problem with your hardware at all.

To test this theory, benchmark with 3DMark 06. If it's stable with that, then your vid card is probably fine. And yes, benchmarking apps are actually the best for testing stability. You have to use a game that really stresses your vid card, and only games can stress PC vid cards that are intended for gaming. No 2D simulation will work or anything like that. GPU's/VPU's are not multi-purpose processors like your main CPU. They can't just do work for the sake of doing work. The only way to stress-test every single transistor on your vid card's PCB is to give it the kind of work it was designed to do - gaming. 3DMark 06 is intense enough that it will force your vid card to work 100%. Every pipeline, every shader unit, every ROP, every ounce of RAM bandwidth, and every single byte of onboard RAM will be tested to its limits. A synthetic gaming benchmark like 3DMark 06, or an intensive 3D game, is the only way to test your vid card (and your system as a whole) for gaming stability.

[jlreich]

At this point pretty much all brands versions of 7800GS are nothing more than Nvidias reference cards with a different sticker on it.
Yes the GPU is the same, but there is more to a video card than the GPU. And the other parts on a video card could be entirely different from one card to the next even if they are bought at the same time from the same manufacturer. Who knows the manufacturer may have switched ram manufacturers etc..

Besides that, one GPU, or any other parts for that matter, could have been tested just below the next step up so it was sold as a 7800GS, and another GPU could have tested just at or above a 7800GS.

So the one that tested just below the next step up may have a much better OC potential, or even have disabled pipelines that could potentially be unlocked. And the other may be barely getting by as passing as a 7800GS and have little to no OC'ing potential.

So many things can effect the OC'ing ability of any one card.

Also take note that factory OC'ed cards usually have less room for additional OC'ing, depending on how much the factory OC is already at.

[skallben]

Ok I tried an application called "ATItool" after recommendation since it got a feature to detect artifacts, it added Nvidia support recently apparantly. Ive ran it on both my brothers and mine now and he get no error even if he raise his speeds with 100mhz, its flawless until really high clocks when you get artifacts reproducting like rabbits. At the same test I get a repeated "error" at way below clockspeed, its usually the same spot in the test view and the same "error-value". I can push mine up or down, it doesnt happen much up until I am way above my stock speeds, I get the artifacts multplying aswell.

I really dont know how to interprent these results, I dont even know how reliable this program is :confused: Seems however that I have some very minor errors on my card but Im yet to notice it visually. But what about lifespan of the card, if its allready some small faults? And how on earth will I get an RMA through; "hey I tried this overclock application, it got a nice feature that tries if you got errrors on the card and it shows I do infact got errors but I dont ever see anything when running even 3Dmark06"...Cant possibly call the store and say that : /

[saphalline]

RMA the card. It sounds like one of the RAM chips is bad. It's not properly storing bits at a certain spot on the chip, causing repeatable and predictable errors.

Don't tell the shop about the OC'ing or anything. Just tell them you're getting artifacts and that you tried swapping vid cards with your brother (who has the same identical make & model) and you both get the same results with your particular card (but not with your brother's). Most shops are also more responsive and willing to help you if you stress that all you want is a replacement, not a refund. Makes better business sense. ;)

At that point, it's not the respsonsibility of the reseller to test the vid card. All they have to do is send it back to the manufacturer and give you a replacement.

[skallben]

I called the store today and they where very helpful and Im gonna RMA it tomorrow. I only hope the manufacturer wont give me any trouble now.
Thanks alot for your input guys, I appreciate it

[saphalline]

You're dealing with the store right now, not the manufacturer. And in fact most manufacturers prefer you deal with the store if you're within the return/refund/replacement time period. You should only deal with the manufacturer directly after the store can no longer help you. Right now, don't worry about the manufacturer. You deal with the store, they deal with the manufacturer. That's how it works.

[skallben]

I bought it over mailorder(or what its called in english) and Ive allready spoken to them, Ive gotten an RMA number and Im supposed to send it to the manufacturer and Im told they will do some tests. It feels a bit like a gamble knowing this but Im sure they got some proffessional methods, damaged memory modules wouldnt elude their tests I hope.

[saphalline]

The store gave you an RMA number to the manufacturer?? Must be a direct reseller or the retail branch of the manufacturer, or something like that. I've never heard of dealing with the store and the manufacturer at once.

If it's giving you errors, they'll find out why. No question about that.