Hi all,

I picked up a XFX 7800GT Extreme from here a couple of days ago, and I've been messing about with some benchies.

I never usually sit and watch 3dMark06 etc but last night I noticed that in the Canyon level, everything is ok until the serpent thingy jumps over the airship whereupon the screen goes very jerky and the screen behind the ship turns into huge triangles as big as the monitor! I think I've described it as well as I can!

Anyway, the rest of the tests complete ok although some of the snow effects on the last test don't look quite right, and I get a score of 3800 or so.

Now then, I've played COD2 and Far Cry for a couple of hours each and there was not a single artifact or graphical anomaly anywhere, so I'm wondering what's going on?

I've not got the card overclocked at all, but interestingly I did try underclocking the core and memory to a standard 7800GT speed, and the graphical glitches in the Canyon test were still there, but much less pronounced.

Should I worry? Is it enough to warrant an RMA you think? Or, does the fact it's just a benchmark mean I shouldn't worry and just get on and use the darn thing?!

Thanks for your comments.

A screenshot of it would help a great deal, download FRAPS and use that to capture a screenshot of it.

Ok, got that software somewhere at home.

I'll give it a go tonight.

Thanks.

i have the XFX 7800GT extreme, and i have never got those problems :S, its possible there is something wrong ..

Maybe download and/or reinstall 3DMark'06 to see if that is the problem?

Yeah, I uninstalled the program and reinstalled from a PC Mag Coverdisk, and got the same result.

I'm wondering if it's anything to do with running it on a PCIE x 4 slot? (Asus P5VD1-X Mobo with an AGP and PCIE slot). When I ran 3dMark06 on my AGP 6800GS, there was no corruption. I've removed the AGP card by the way!!

I get a fair enough score, but I wonder if 3dMark06 pushes the bandwidth of the slot on that particular test?

As I say above, on games its fine. No freezing, pausing, glitches or anything else, and it's way quicker than the 6800GS as you'd expect.

I don't get any corruption on 3dMark05 either, and ATI tool reports artifact free after an hour of running.

Its got nearly 12 months left on the warranty, so maybe I'll just keep an eye on it.

Ok, got some screenies for you to look at.

I know it's not right, but as it only appears on 3dMark (in this case, 05), should I be worried?

Thanks again!

Screenshot 1

Screenshot 2

Screenshot 3

If games run fine then dont worry.

What drivers you using? Maybe download the latest and reinstall?

Check to see if your PCIE slot bus speed is locked... might be out of spec?

Those look bad, strange thing is that you only get it in 3DMark'06

Have you tried underclocking the card?

Might be an nvidia driver bug too...nvidia drivers >.<

Yeah, I've tried underclocking the card, and seems to make little or no difference on the several runs I've tried.

Interstingly, the very first run through the benchmark just after booting up is fine, it's only on the 2nd or 3rd run through that these glitches start to appear. I managed to catch the corruption with FRAPS, but they only appear like that for a second or so now and again.

On the other hand, I've played COD2 for about 2 hours straight without so much as a hitch, and in that regard it seems way more stable than my old 6800GS which used to sometimes lock up after an hour or so.

I'll mess about with some different drivers to see if that helps, but I'm suspecting either the PCIE x4 slot, or some kind of hardware problem that only shows up on the benchmark once the card has properly warmed up.

If OCUK still had these in stock, I'd be inclined to RMA it and try another one, but it would probably take ages to sort a replacement now that they aren't a stock item.

As you say it only happens for a very short amount of time, maybe in games it happens even faster and is not visible to the human eye.

Bottom line it isn't normal, yesterday I ran it on my XFX 7800GT and I did not see that at all.

Mmm, I'm inclined to agree with you that it's not normal, but not sure what to do about it now!

Update...

I was fed up with the instability of my P5VD1-X board, so ordered an Abit NI8 SLI GR mobo and some DDR2 ram.

Installed everything yesterday, and not only is the board crash free (so far anyway! But the old one was 1 or 2 times a day at least...) but the graphical tearing has now gone too.

I never really got to the bottom of what was causing it, but I suspect the 4x slot was something to do with it.

Now if only I could pick up another 7800GT for £93, then I'd be well away!

Come on Gibbo, now you no longer stock 7800GT's, how about some 7900GT's for a bargain price?!

It's a shame you had to buy a new mobo but at least the problem is solved.

I don't think you can SLI a 7800GT and 7900GT, you need to find a 7800GT, either new or 2nd hand.

Yes, you're right, unfortunately you can't SLI the 7800 and 7900 chips. If he could do me two at a decent price though?!

I've now removed the stock heatsink, which I thought was noisy, and which couldn't be slowed down, and replaced it with my Zalman VF700.

I also modded the LED part of the old heatsink and wired it back in to the card with the Zalman fitted so that the XFX logo still lights up! (Sad eh?!)

With the Zalman fitted though, it looks like I couldn't get another card in SLI fitted without putting the stock fan back on anyway!

I'm happy enough with one 7800GT for now, and at least I've got options going forward compared to where I was.

Thanks for your help/suggestions by the way!

What temps do you get with your 7800GT and Zalman VF700 ?

My temps are 50C idle and 80C load with the fan on a fancontroller at 7V in a case with nearly no airflow.

43c Idle and 73c under load, that's on the slowest speed connector on the fan controller.

My case is well ventilated though. 120mm Amber Series pulling air in, 2 x 80mm Ambers at the rear, 1 x 80mm Amber on the side and another one on the blowhole up top!

They're all on a fan controller though and turned down low, so not noisy, and my case temps are usually around 31 to 35c.