What technical features make a good Graphics card (stability/oc/ov)?

[wand3r3r]

Firstly to avoid the idea that this is a brand thing, it isn't meant to be. Theoretically we are examining two cards from the same manufacturer/model.

Say reference vs. custom or possibly custom vs. custom.

Reading past the marketing, what matters most for the stability and perhaps overclocking/overvolting and long life of a graphics card?

As I browse e.g. 290's (but that doesn't have to be the focus of this discussion) I'm curious what cards are best for OCability/ov/stability after your remove the silicon lottery factor. When looking at e.g. the sapphire Tri-X, the reviews mention that it's basically better cooling on the reference board. The reference card is obviously overwhelmed by the hot core and therefore the clocks are not necessarily consistent.

Some points which are mentioned often are the fan/cooler, VRMs & cooling, power phases, solid capacitors. What else should a (relative picky) buyer be paying attention to (and briefly why).

Clearly the Lighting and classified are the most revered cards but are the e.g. SCX and Gaming essentially the same thing as the higher end cards to an air cooled user (assuming some silicon binning may be in the Lightning/classified)?

Obviously warranty is another critical point but it doesn't mean you can't overclock etc.

A starter list:

Cooler/fan & effectiveness vs. noise
VRM cooling
Power phases
Solid capacitors (are there even others anymore)
Chokes
Coil whine (reputation?)
Heatpipes
PCB flex

 

[blastingcap]

It's not as simple as saying more power phases = better. That is if everything is equal, but it's not always the case. It'd be like saying more megapixels are better for a camera--that's sort of true but I'd rather have a larger sensor with fewer megapixels in some cases. Also, I would add "chokes" to your list of things to look at. Also if it has a rep for coil whine or not. PCB stiffening braces/spines indicate attention to detail to me so they don't want the card to flex and die early. Same thing if they nickel plate the copper heatpipes--it's not absolutely necessary, but it's a nice touch because they apparently care enough about the card to guard against oxidized copper.

 

[wand3r3r]

It's not as simple as saying more power phases = better. That is if everything is equal, but it's not always the case. It'd be like saying more megapixels are better for a camera--that's sort of true but I'd rather have a larger sensor with fewer megapixels in some cases. Also, I would add "chokes" to your list of things to look at. Also if it has a rep for coil whine or not. PCB stiffening braces/spines indicate attention to detail to me so they don't want the card to flex and die early. Same thing if they nickel plate the copper heatpipes--it's not absolutely necessary, but it's a nice touch because they apparently care enough about the card to guard against oxidized copper.

So power phases aren't necessarily a feature to compare in a straightforward way between e.g. a gaming vs. acx card of the same brand and model? (good MPx analogy)

The PCB flex and coil whine are more subjective and relevance is in the eye of the buyer. (Coil whine would be a deal breaker for me for example) Nickel plating is also interesting.

 

[46andtool]

Firstly to avoid the idea that this is a brand thing, it isn't meant to be. Theoretically we are examining two cards from the same manufacturer/model.

Say reference vs. custom or possibly custom vs. custom.

Reading past the marketing, what matters most for the stability and perhaps overclocking/overvolting and long life of a graphics card?

As I browse e.g. 290's (but that doesn't have to be the focus of this discussion) I'm curious what cards are best for OCability/ov/stability after your remove the silicon lottery factor. When looking at e.g. the sapphire Tri-X, the reviews mention that it's basically better cooling on the reference board. The reference card is obviously overwhelmed by the hot core and therefore the clocks are not necessarily consistent.

Some points which are mentioned often are the fan/cooler, VRMs & cooling, power phases, solid capacitors. What else should a (relative picky) buyer be paying attention to (and briefly why).

Clearly the Lighting and classified are the most revered cards but are the e.g. SCX and Gaming essentially the same thing as the higher end cards to an air cooled user (assuming some silicon binning may be in the Lightning/classified)?

Obviously warranty is another critical point but it doesn't mean you can't overclock etc.

A starter list:

Cooler/fan & effectiveness vs. noise
VRM cooling
Power phases
Solid capacitors (are there even others anymore)
Chokes
Coil whine (reputation?)
Heatpipes
PCB flex

Nice post, and although I have nothing to add, I'm interested to see others weigh in on this as well. I have the upgrade itch and have been asking myself a lot of the same questions you asked here.

I'd just like to add that I think the reason the new reference high end AMD cards are throttled has more to do with the sub par cooling rather than the reference PCB being the issue

 

[blastingcap]

So power phases aren't necessarily a feature to compare in a straightforward way between e.g. a gaming vs. acx card of the same brand and model? (good MPx analogy)

The PCB flex and coil whine are more subjective and relevance is in the eye of the buyer. (Coil whine would be a deal breaker for me for example) Nickel plating is also interesting.

They aren't straightforward because you need to take quality into consideration as well. Perhaps a more PC-apt analogy than my camera-megapixel analogy is heatpipes. Which would you rather have, four 8mm diameter heatpipes or five 6mm diameter heatpipes?

 

[24601]

If you don't feel like modifying your bios, the maximum power limit is also important.

FYI most 7950s had stupidly unrealistically low power limits that made it super annoying to troubleshoot overclocks.

One of my 290s requires a slight undervolt to not throttle @ +50% powertune limit @ pure stock clocks

Another important thing is the ability to see actual post droop voltage and/or VRM Temps and amperage in some way/shape or form by software.

For AMD/ATi cards ASIC quality is important as higher ASIC quality is directly binned for same clock at lower voltage.

Which exact GDDR5 chips is important as well.

How well/badly the GDDR5 is routed to the GPU is important as well.

VRAM temperatures (probably not going to get a reading for it in software) and VRAM cooling

Power connectors from PSU, 8+8 or better allows cleaner delivery from PSU to card with less droop. Only reason the current crop of 400-700w cards come with less is to meet various PCI specifications.

TIM application style, quantity and which TIM is used is also important for those who don't want to take the cooler off and apply their own TIM.

Timings and generally cheating in VBIOS. Whether this is fixable or not.

Once the full custom 290/290x's come out we'll see if AMD/ATi clamped down on the counterproductive behavior that is infamous from their trash AIB's which lead to such deservedly low reputation on the hardware side of the AMD/ATi equation.

IMC/ROP stability/quality doesn't seem like something AMD/ATi or their AIB partners have gotten a good way to bin yet, as we can see by the cards shipping as GHz edition that has significant returns where the reason makes it obvious that the IMC/ROP wasn't up to snuff for the throughput pushed through them.

If they could bin them better you can bet you would see huge margins made by selling guaranteed binned 1500 MHz GDDR5 equipped 290's and 290x's for mining purposes.

 

[blastingcap]

If you don't feel like modifying your bios, the maximum power limit is also important.

FYI most 7950s had stupidly unrealistically low power limits that made it super annoying to troubleshoot overclocks.

One of my 290s requires a slight undervolt to not throttle @ +50% powertune limit @ pure stock clocks

Another important thing is the ability to see actual post droop voltage and/or VRM Temps and amperage in some way/shape or form by software.

For AMD/ATi cards ASIC quality is important as higher ASIC quality is directly binned for same clock at lower voltage.

Which exact GDDR5 chips is important as well.

How well/badly the GDDR5 is routed to the GPU is important as well.

VRAM temperatures (probably not going to get a reading for it in software) and VRAM cooling

Power connectors from PSU, 8+8 or better allows cleaner delivery from PSU to card with less droop. Only reason the current crop of 400-700w cards come with less is to meet various PCI specifications.

TIM application style, quantity and which TIM is used is also important for those who don't want to take the cooler off and apply their own TIM.

Timings and generally cheating in VBIOS. Whether this is fixable or not.

Once the full custom 290/290x's come out we'll see if AMD/ATi clamped down on the counterproductive behavior that is infamous from their trash AIB's which lead to such deservedly low reputation on the hardware side of the AMD/ATi equation.

I generally agree with the above.

And now that I think about it, it does seem like there haven't been as many good AMD designs lately. The 7xxx series was a black eye to XFX in particular, though their 280X cooler design is decent. The tiny fans on the TFIIIs were frustrating though TFIV coolers seem to fix that problem. Sapphire had issues with their chokes or something on the 7870s, ASUS had mis-mounted DCuII GPUs early on, Gigabyte is a jerkoff company that voltage-unlocks only review samples and the locks the very same model for actual retail sales. Plus they rushed out the 290X Windforce only to recall them a week later due to offspec components.

On the bright side, HIS, Visiontek, and Diamond offer more aftermarket coolers after mostly selling reference cards for a long time, and some are quite good like the HIS IceQ Turbo. Powercolor has also upped its game and even sells some cards with waterblocks built in, though some of their other designs are mediocre at best. Also, reference AMD cards may be loud with fans cranked beyond 55%, but they have never failed me personally except a refurb I bought once, and who knows what the previous owner did to the card.

 

[24601]

Oh yeah, whether the cards come with sleeve bearing, double ball bearing, or fluid dynamic bearing (having seen one with that yet) fans, determining the average life of the fan without regreasing which would probably void your warrantee anyways.

And yeah, the fans Sapphire and it looks like now most of the AIBs are using have a seriously low average life without regreasing.

 

[BallaTheFeared]

Silicon/Binning.

Everything else is military class 4 breaks two weeks later marketing unless you're doing power runs on at least chilled water/cascade.

 

[blastingcap]

Oh yeah, whether the cards come with sleeve bearing, double ball bearing, or fluid dynamic bearing (having seen one with that yet) fans, determining the average life of the fan without regreasing which would probably void your warrantee anyways.

I'd love to get my hands on that info but I have never seen ball bearing fans advertised on an aftermarket card. Not even single ball.

 

[24601]

I'd love to get my hands on that info but I have never seen ball bearing fans advertised on an aftermarket card. Not even single ball.

Not on AMD/ATi side, but EVGA made a big thing about double ball bearings on their ACX cooling solution they rolled out with the 780.

 

[blastingcap]

Not on AMD/ATi side, but EVGA made a big thing about double ball bearings on their ACX cooling solution they rolled out with the 780.

Oh yeah I remember that.

Silicon/Binning.

Everything else is military class 4 breaks two weeks later marketing unless you're doing power runs on at least chilled water/cascade.

Good point re: silicon/bins but that can vary over time (the early Sapphire 7xxx were binned, later ones not), and I have also found that ASIC is not necessarily meaningful between different cards. I tried 2 different MSI TFIII 7950s and both were 89+ ASIC yet ate more wattage than my 64% ASIC Sapphire 7950. It may be that the weak fans on the TFIII meant worse cooling and thus higher temps and thus higher power draw despite the higher binning.

 

[wand3r3r]

I ran into this reading the khash improver via RAM bios fixes. I think this is very relevant to this thread.

I hear the poor hash rate is quite common on XFX 7970's which I will be getting in a few days, is this something you could help with if I sent you copies of the BIOS?

Please check the actual GDDR5 modules first.
The last XFX 7970 bios I saw was a complete mess.
It had three different modules supported in the VRAM block and none of the profiles were complete in timing or frequency vise.
They seem to ignore the reference design guidelines completely and use anything they can get for cheap.

The XFX Black Edition and the reference PCB based cards are ok.
Their own designs are something else. They have dropped four PCB layers (eight instead of twelve), half of the GPU VRM (VDDC) fets and use a "stupid" VRM controller (analog) instead of the CHIL 8228G (digital).

A great disposable mining card, those cheapskates.

https://litecointalk.org/index.php?topic=12369.15

 

[monkeydelmagico]

Some points which are mentioned often are the fan/cooler, VRMs & cooling, power phases, solid capacitors. What else should a (relative picky) buyer be paying attention to (and briefly why).

None of it matters one bit if the final results suck. The only way to know the final results is to wait for others to test and report. Then you have to take the reviews with a huge grain of salt. I've owned cards that many would consider "inferior" and they outperform cards costing alot more. I've also bought cards based upon reputation and construction that weren't worth the $$$. I find it's better to wait and see rather than be a guinea pig.