AMD HD 7750 going in your HTPC? - Page 2

Anyway, the heatsink is about 20mm over the PCI bracket. So make sure you case is tall enough before buying Sapphire HD 7750 Ultimate Edition. It's only 5mm in the case of the ASUS fanless so that it fits *every* full-height case with 2-slot space for graphics.

Well, the difference should be obvious even just by glancing at pictures without measurements.

Instead I highly recommend HIS H775F1GD (fits every full-height HTPC case with 2-slot space, close to silent at idle and video playback).

Were you able to get a coupon for Dirt 3 buying from Tiger Direct?

No...but I honestly don't care about that game. I have Forza 4!

Sim City 5 however....I'll be playing that when it's released in a few months.

I was just wondering because of the value. I guess you could sell it for a not insignificant "price reduction". At this point I'll take whatever I can get. I do loved Dirt 2 though.

hi,

My 6670 ultimate did not fit the GD05 case way over, i'm thinking of getting a reference 7750 and fitting a Arctic plus 2 cooler with fan controller.

http://www.arctic.ac/en/p/cooling/vg...o-l2-plus.html

does anyone know which ones are reference design 7750?

Thanks

You'd probably get a better deal if you just buy one with a good heatpipe cooler.

EDIT: so for this class of card heatpipe coolers might not be available (with fan) but there are any number of coolers with big fans, no need for the aftermarket one.

So, the 6570 under Catalyst 11.5 had no chroma bug (http://www.anandtech.com/show/4380/d...pus-shootout/4). The 7750 under 12.1 has the chroma bug (http://www.anandtech.com/show/5541/a...ition-review/6).

Anyone know when the chroma bug entered the drivers and whether I can avoid it on a 6670? Trying to decide between a 6670 and 7750.

TIA

That cooler looks suspiciously like the one i had on my 5670, which wasn't extremely loud, but when everything else you got in the HTPC is one very silent 120mm on the CPU and one equally silent case fan, i did hear it quite well.

I went with the passive Sapphire version, and it works quite beautifully. Granted, i don't have a HTPC case, rather a very small tower case (the Silverstone TJ08-B), which is just wider to accommodate full-sized CPU air coolers and this type of cards as well. Its now nearly inaudible (when its the only thing on in the room, you do notice it ever so slightly if you pay really close attention), much more silent then my previous build.

I moved from 5450 to 7750 and I'd say that picture isn't worse at least. BTW I'm not sure that problem above is related to chroma bug actually.
IMO "chroma bug" is chroma 444>422 downsampling somethere in HDMI/DVI interface (thats why both ATI and Nvidia were affected). And what we can see on anand pics is chroma 420>444 upsampling by Nearest Neighborhood. NN is a worst quality scaler. But it works fast and ATI uses it for chroma sub-sampling.
I use madVR renderer with its own chroma scalers to keep ATI driver's hands away from it . And I use direct DVI to TV connection (w/o sound) to avoid chroma bug. HDMI to AVR for sound.
Video rendering is slow for 2-mon setup, so I set it to Clone and enabled "Gpu scaling" in CCC.
Almost forgot: don't even try 12.4 drivers.

Yeah, I'm referring to the CUE. IIRC, ten years ago it had the "chroma bug" moniker, although I usually call it the "red jaggies". Either way, I do not have fond memories of it and want to avoid it.

I'm tempted to get the 6670 over the 7750, because we know that there's at least one version of CCC, namely 11.5, that avoids the red jaggies.

You are really mislabeling things here, the original chroma bug was always the upsampling problem on ATI cards, what you're refering to is quite another problem that seems to be related to other components in the HDMI chain, and not purely the GPU.
The chroma bug is a rather old problem, going back at least 3-4 years (maybe longer, but thats when HTPC got somewhat popular). What you describe is probably equally old, but it didn't get in the focus until recently.

ATI chroma upsampling bug actually shows in screenshots, the other problem does not.
Your "chroma bug" is also not that obvious in movie content, most people only notice it when reading texts on their tv or gaming, while the upsampling problem shows up even in movies.

Yes, quite a bit longer.

http://www.hometheaterhifi.com/the-d...a-problem.html

I think the problem is as old as MPEG-2.

That is yet another problem.
What we're talking about (and AnandTech), is an ATI driver bug that only uses Nearest-Neighbour scaling for the Chroma.
Its limited to ATI, and only certain driver revisions, although which drivers seems to depend on which hardware you have.

The end result may look similar to the old DVD players fault, not its really a different problem.
The algorithm that ATI uses itself is correct, its just not using any interpolation, which gives jagged edges and a "blocky" feeling.

OK, got it. Using Nearest Neighborhood scaler for chroma sub-sampling is a... bug. Tell madshi about.

Ah, so it isn't really the dreaded CUE aka chroma bug aka red jaggies? Anandtech linked to an article related to the one I posted, which is what had me believing it was the red jaggies. If they are avoiding the red jaggies bug, but simply using nearest neighbor, I would expect that to be far less noticeable than the red jaggies. Still unfortunate though.

I am quite sorry if the reference links I had put in resulted in some confusion.

As Hendrik explained, AMD uses a nearest-neighbour algorithm which is not that great at hiding artifacts. In the link I put in my original piece, Spears & Munsil indicate that a CUE is present when the simplest "copy each chroma line twice" algorithm is used.

When I do the scoring for the HQV clip, I take 3 - 4 screenshots and look at the zoomed picture (refer to my Llano review here). If there is any type of flaring, i.e, in any horizontal row of pixels, if I see a coloured pixel followed by one of darker shade and again followed by a higher intensity pixel before becoming part of the full coloured slanted bar, I consider it as a CUE even though it is not the same CUE that Spears & Munsil point out in their article. (The HQV guide also suggests that this type of flaring be flagged as CUE).

@jakmal:
From your testing would you know if it is possible to output HDMI audio from one of the mini display ports with the latest drivers?

As usual I posted this question for AMD support several weeks ago and never got an answer - hardware as always is very nice, drivers and support catastrophic.

The whole display port/HDMI thing is a pita - the fact that AMD is not adding any mini display port to HDMI adapters to the card is not helping either.

This topic on the XBMC forum seems to very strongly imply to me that the Sapphire Ultimate 6670 will not fit in a Silverstone GD05. The information is scattered throughout the topic, but look at posts #6 and #10 and the equipment listed in the sig. This in turn very strongly implies to me that the Sapphire Ultimate 7750 will not fit in a Silverstone GD04.

I have a Silverstone GD04 and just purchased the HIS Silent 6570 instead.

You have absolutely nothing to apologize for there. It's my mistake for not understanding the problem well enough. The work you do in reviewing these cards is absolutely invaluable. Anandtech is my #1 trusted source for these types of reviews.


Is it your conclusion that AMD switched chroma upsampling algorithms between CCC 11.5 and CCC 12.1 or does something else explain why the 6570 under CCC 11.5 passed and the 7750 under CCC 12.1 failed?

Its sadly not as simple as the driver version.
It may still work with 12.1 on the 6570, but fail on the 7750. There is more weirdness at work here.

I was afraid of that, and it's another reason why I went for the 6570. I'm just hoping the 6570 (and the rest of my two HTPCs, one i3 530 and the other Athlon II X4 635) have the horsepower and memory bandwidth for MadVR, should I eventually decide to go that way. Time will tell.

Thanks.

madVR is not affected by that problem, so if you went that way with a 7750, it would still be fine.

I use my 7750 with madVR, and its just beautiful.

Understood. I purchased the 6570 to avoid the problem while using the native XBMC player. The UI and UE of the native XBMC player is just so much better than MPC-HC, but if I have picture quality problems in XBMC, MPC-HC + MadVR will be my next step, providing my hardware is up to it. Otherwise, I see an Ivy Bridge upgrade at some undetermined point in the future.

I thought you were an NV guy

Do you see significant improvements with copyback decoding with this card, and madVR? For some reason my 5770 could not do 1080/24p or 720/60p with any such HW decoder.

With my 7750 I have smooth playback with copyback and madVR (DX11 thing enabled) even on Avatar 1080p60 45mbps sample. Well, 1 of ~200 frames droped though, but this may be ReClock's fault or I have to play with madVR's buffers.
With 5450 I couldn't get smooth playback with CB. For 720 it was smooth more or less, but with Cyberlink HAM it was really smooth.

NVIDIA doesn't have a good passively cooled card (yet), and the 7750 was cheap enough to try it.

I don't use it for decoding though, i have my Ivy Bridge CPU do that (either in software mode or in QuickSync mode)
In theory they finally improved memory peformance on the 7xxx series, so yeah CB should be much better now.

What is the memory spec that will help though? Cause in bandwidth alone, the 5770 should be better, no?

Nothing you can read from specs, the 7xxx series are just better at copying stuff from the GPU to the CPU. Most likely they worked on that for better GPGPU compat.

PS:
The actual bandwidth of the two is quite similar, 72GB/s for 7750 and 76.8GB/s for the 5770.

Hmm I think I'll try that, but I keep getting these thoughts about going back to playing games (though in practice it's never worked out), and keep waiting for the 7850 to get reasonable in price. My whole system is getting old though, I'm still running DDR2 800, and I don't know (and madshi didn't either) if it could be part or the whole of the problem.

Then my problem could be something else, cause HAM was pretty much the same as LAV and Potplayer's implementations.