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The Radeon HD 5550 Architecture

Radeon HD 5550 And 5570: Pumped Up With GDDR5
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We’ll start by looking at a block diagram of the new Radeon HD 5550. The GPU is actually the same RV830-based silicon used in the Radeon HD 5570/5670, but with some functionality disabled.

In the big scheme of things, not much is changed. The only notable modification is that the Radeon HD 5550 GPU has four single-instruction multiple-data (SIMD) engines, while the Radeon HD 5570/5670 has five. Each SIMD engine features four texture units and 16 stream processors, and each stream processor has five ALUs (AMD calls them stream cores). Therefore, the Radeon HD 5550 GPU has 320 stream cores and 16 texture units, compared to the Radeon HD 557/5670’s 400 stream cores and 20 texture units. Aside from this 20% reduction, nothing else has been disabled. The Radeon HD 5550 sports the same dual 64-bit memory controllers sharing two render back-ends as the Radeon HD 5570/5670. Each render back-end contains four color render output units (ROPs) resulting in a total of eight ROPs and a combined 128-bit memory interface.

The end result is that the Radeon HD 5550 GPU is quite powerful for a low-end part (certainly a lot more powerful than the Radeon HD 5450 and its 80 stream cores). Often, when low-end GPUs are designed, the render back-ends are sacrificed.  But the Radeon HD 5550 maintains the same ROP count as the Radeon HD 5570 and 5670. To get the whole story though, let’s look at the complete list of specifications:


Radeon HD 5550Radeon HD 5570Radeon HD 4670
Shader Processors:
320
400320
Texture Units:
16
2032
Color ROPs:
8
88
Fabrication process:
40 nm
40 nm55 nm
Core Clock:
650 MHz
650 MHz750 MHz
Memory Clock:
900 MHz DDR3
900-1000 MHz GDDR5
900 MHz DDR3
900-1000 MHz GDDR5
1000 MHz DDR3
Memory Bus:
128-bit
128-bit128-bit
Data Rate:
1.8 Gb/s DDR3
3.6-4 Gb/s GDDR5
1.8 Gb/s DDR3
3.6-4 Gb/s GDDR5
2 Gb/s DDR3
Compute (GFLOPs):
352
520
480
Transistors (Millions):
627
627514
Max Power (W)
39
42.7
59
Idle Power (W)10
10
14


The numbers show us how AMD is wedging the Radeon HD 5550 into the 5000-series: by dropping the GPU's core clock in order to keep performance in line with the product’s placement. But overclockers can see the Radeon HD 5550’s potential. The RV830 GPU should be able to handle a 700 MHz operating frequency with ease, and at that speed, the Radeon HD 5550 should be quite competitive with the Radeon HD 5570.

On top of this, the GDDR5 version of the Radeon HD 5550 offers more than twice the memory bandwidth of AMD's Radeon HD 5570 DDR3. It’s quite possible that could offset the core clock (and possibly the 80-core advantage) of the Radeon HD 5570. If this proves to be the case in the benchmarks, budget-oriented gamers will have an attractive board to tweak and tune. Of course, it'd be a little awkward for AMD, with the Radeon HD 5550 DDR5 and Radeon HD 5570 DDR3 performing uncomfortably similarly. We’ll keep our eyes on these two cards in the upcoming test results.

Finally, let's take a look at the new GDDR5-based Radeon HD 5570 and see how it stacks up against the Radeon HD 5670 and Radeon HD 5570 DDR3:


Radeon HD 5670Radeon HD 5570 GDDR5
Radeon HD 5570 DDR3
Shader Processors:
400
400400
Texture Units:
20
2020
Color ROPs:
8
88
Core Clock:
775 MHz
650 MHz650 MHz
Memory Clock:
1000 MHz GDDR5
900-1000 MHz GDDR5
900 MHz DDR3
Memory Bus:
128-bit
128-bit128-bit
Data Rate:
4 Gb/s GDDR5
3.6-4 Gb/s GDDR5
1.8 Gb/s DDR3
Compute (GFLOPs):
620
520
520
Transistors (Millions):
627
627627
Max Power (W)
61
42.7
42.7
Idle Power (W)14
10
10


Armed with the same GDDR5 memory as the next-highest model in AMD's Radeon HD 5000 family, the only functional difference between the Radeon HD 5570 and 5670 is 125 MHz of core clock speed. The Radeon HD 5570 GDDR5 might reach Radeon HD 5670 performance when overclocked, but 775 MHz on the core might be a bit of a stretch without a voltage increase. We’ll see how things turn out when we try our hand at overclocking these cards.

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Top Comments
  • 12 Hide
    welshmousepk , August 18, 2010 6:54 AM
    crysis 2 'on the horizon'?

    either you have not heard the terrible news, or you are a far more patient man than I.
Other Comments
  • 0 Hide
    amk09 , August 18, 2010 6:44 AM
    Very interesting but strange article.
  • 12 Hide
    welshmousepk , August 18, 2010 6:54 AM
    crysis 2 'on the horizon'?

    either you have not heard the terrible news, or you are a far more patient man than I.
  • 2 Hide
    gkay09 , August 18, 2010 7:02 AM
    No surprises IMO as it was the same with the HD 4650/ 4670...the 1GB DDR2 was slower than the 512MB DDR3...
  • 8 Hide
    Anonymous , August 18, 2010 7:55 AM
    You've mixed up the HIS5550 and HIS5570 end-on port pictures I think. You state the 5550 GDDR5 has no VGA and one is shown and vice-versa for the 5570 GDDR5. In fact it looks like quite few of the pictures are misplaced.
  • 0 Hide
    edlight , August 18, 2010 9:03 AM
    When you do the HQV tests, could you investigate drivers? They have a desktop color and a video (movies) section. With my 4670, it's not always clear which videos the video section works on. It varies between Win 7 and XP. Basically it works on movies in the overlay, and/or players with hardware acceleration turned on. In Win 7 it works on the flash videos, in XP it doesn't. In XP in video you can adjust Gamma, in Win 7 you can't. In XP the brightness etc. adjustment in video is independent from the desktop. In Win 7 desktop adjustments to brightness etc. affect the videos, even in the overlay. In XP the Dynamic Contrast button is there, but does nothing.

    After driver 10.4, in XP, video brightness and other adjustments just don't work. If you want to adjust the video you have to go back to 10.4.

    Contrast this with nvidia. As far as I know, their drivers work properly, with Gamma adjustment for video, and video brightness etc. separated from desktop brightness etc.

    But, in the last nvidia drivers I tried, there are problems with profiles. While you're in video, you can't save the settings as a profile. You have to go to desktop. Then you can save them. You used to be able to right-click on the tray icon and select your profiles. In the last nvidia driver I checked, you couldn't do that. At least you can do that in the ATI drivers. You can't sort the darn things, though.

    So, to select a profile in nvidea you'd always have to open the control panel. In ATI, if you've come upon a dark video and you have several profiles to try on it, it's fast and easy by right-clicking in the tray.

    I don't think the programmers actually use the control panels themselves. Such awful logic!

    One last thing I'd like to know from the coming article is if the nvidia video section works on flash videos (with the 10.1 flash) in XP. It must in Win 7.
  • 8 Hide
    dconnors , August 18, 2010 9:33 AM
    welshmousepkcrysis 2 'on the horizon'? either you have not heard the terrible news, or you are a far more patient man than I.


    I would say anything under a year is "on the horizon" so a March 2011 street date lines up pretty well with that statement.

    -Devin
  • 1 Hide
    LordConrad , August 18, 2010 9:58 AM
    Wrong connector picture for the HIS 5570?
  • 1 Hide
    LordConrad , August 18, 2010 9:59 AM
    Or maybe the caption is wrong...
  • 8 Hide
    Onus , August 18, 2010 10:15 AM
    I would like to have seen the HD4670 in the benchmarks; I think that is more likely competition than the HD4650, which was beaten pretty badly.
  • 6 Hide
    belardo , August 18, 2010 10:56 AM
    Yeah, the 4670 does belong on this benchmark article, but for the most part - the 5570 OC is on par with a standard 4670. Give or take.

    But what really belongs here is the 5450!

    That would show how much MORE powerful the 5550/70 cards are... Yeah I know, about 4x... but still it should be there. Maybe the 5470 will come out ;) 

    Current pricing of the lower 5000 & 4000 series (Order of performance)
    5450 = $40~70 ($55+ = 1GB useless versions)
    4650 = $50~80
    5550 = $65~90 (DDR2 or DDR3 ver)
    5570 = $70~90 (DDR3)
    4670 = $70~90
    5670 = $85~105
    5750 = $125~150 (Ouch - considering they cost less to make that 4670s)

    First, when it comes to DX11 games, they are too much for the 5550 and below - but under DX10 - they do pretty good. So for your $70~75, you might as WELL buy the 4670 over the 5550s and 5570-DDR3. Now if the the 5550-DDR5 sells for the same price or less of a 4670, then it maybe worth it.

    Considering the age of these cards, the 5670 should be $80~90... as it doesn't touch the $100 4850! But the 4850 & 57xx requires more power/bigger PSUs.

    A non-eyeinfinity version of a 5750 for $100 would be a sweat card to get that would hammer the nail into the 4800 series.



  • 0 Hide
    Reynod , August 18, 2010 11:11 AM
    Thanks Don.
  • 0 Hide
    elbert , August 18, 2010 11:53 AM
    I would have liked to have seen a 5570 dd3 1gb overclock.

    Quote:
    Unlike the HIS Radeon HD 5550 GDDR5 sample we have, the HIS Radeon HD 5570 GDDR5 card is not equipped with a DisplayPort output, and therefore triple-monitor Eyefinity is not a possibility. The card has a DVI, an HDMI, and a VGA output instead.

    The image above this statement has no VGA but does have a DisplayPort. I'm kind of at a loss here as either the statement or the image is incorrect. Also Unlike should be like if the statement is correct having them both without Displayport.

    I really dont like the graphs. They are very hard to read. I would like the see best to worst in order graphs.
  • 0 Hide
    JeanLuc , August 18, 2010 12:03 PM
    What's up with the noise chart? I was shocked when I saw the Sapphire 4650 noise levels then I realised it was only 6dcb higher then the HD5550. It's very misleading can you please fix it as that Sapphire looks as it it's 6 times louder then anything else.
  • 1 Hide
    forsayken , August 18, 2010 12:55 PM
    The 4850 is still very much available for $90 and blows every card in this benchmark out of the water and usually beats the 9800GT. I'd still get this board over all others if I had only $100 to spend on a card and you want to game. I do have a 5670 and will admit that I am very impressed with heat/noise so that is a wise choice as well for a lower-power system. It runs SC2 on "high" and BC2 on good enough settings to be visually appealing.
  • 2 Hide
    cknobman , August 18, 2010 1:46 PM
    Would like to have seen the 4670 on here for comparison. I picked up my 4670 last October on an egg special for $39.99 after rebate (and yes I finally got my rebate after 4 months).

    My suggestion to anyone wanting to buy a $50 - 100 card is wait for specials and rebates because you can often get one well below market rates if you shop around.
  • 0 Hide
    kresso , August 18, 2010 2:14 PM
    cknobmanWould like to have seen the 4670 on here for comparison. I picked up my 4670 last October on an egg special for $39.99 after rebate (and yes I finally got my rebate after 4 months). My suggestion to anyone wanting to buy a $50 - 100 card is wait for specials and rebates because you can often get one well below market rates if you shop around.

    I got that same deal and couldn't be happier (ok I could but, for that price the 4670 was a steal)
  • 0 Hide
    wolfram23 , August 18, 2010 2:33 PM
    Interesting low end GPU. ATI is really pushing to get DX11 cards out there, for people of all budgets.
  • 0 Hide
    rohitbaran , August 18, 2010 2:41 PM
    Since they have launched these 2 cards now, it looks like either the refresh isn't around the corner or it is probably only for the top end models.
  • 2 Hide
    COLGeek , August 18, 2010 3:02 PM
    I have used several 4550/4650 GPUs and have been very pleased with all of them. It comes as no surprise that their HD5XXX cousins perform equally as well in terms of cost and processing. Not all users are power users, nor are all users OCing their rigs. This class of GPUs really does meet the needs of most users and at a pretty decent price point. It is hard to not respect ATI for producing capable GPUs for the masses.
  • -5 Hide
    WarraWarra , August 18, 2010 3:05 PM
    Interesting.
    I can see a price point for this hardware but why upgrade from a NV9800gtx to anything less than a Ati5770.

    NV9800gtx newegg $135
    5670 newegg $110
    5770 newegg $135

    I can not see anyone not willing to sacrifice 2 hamburgers or a few beers and rather get a 5770 instead of a 5670 or even a 9800gtx. No one can be this poor or stupid.

    IE: what the ??? is the use of these low end mobile phone video cards ?

    If AMD stops wasting money on these low end junk and rather have fewer models, spend more time producing useful video card then they can have decent prices for the server headless video card like the 5850 that should be "$150" video card instead of this stupid list of prices and models of uselessness.
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