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AMD Radeon RX 7600 Review - For 1080p Gamers

W1zzard

on May 24th, 2023,

in Graphics Cards.

Manufacturer: AMD

(341 Comments) »

Introduction

AMD today released its Radeon RX 7600 graphics card, and you'll see a rare overlap of launch-day reviews between AMD's RX 7600, and NVIDIA's RTX 4060 Ti on the same day. Both cards go on sale today. The RX 7600 is a mid-range offering from AMD's latest RDNA 3 family, and sees the company jump from the enthusiast-segment RX 7900 series straight to the most hotly contested market segment, the $300-ish mid-range, where the RX 7600 is expected to square off against NVIDIA's RTX 4060 series. The new RX 7600 is designed for AAA gaming at 1080p, with high to maxed-out details, you can take advantage of features such as FSR to further dial up display resolutions, and effectively game at 1440p.

The Radeon RX 7600 in this review is based on the same RDNA 3 graphics architecture that also powers the RX 7900 series, but understandably scaled down. What's unexpected, though, is that unlike the RX 7900 series, which use 5 nm GCDs, the Navi 33 silicon at the heart of the RX 7600 is a monolithic 6 nm chip, an entire generation older than 5 nm due to its DUV lithography, compared to the more advanced EUV. AMD probably calculates that for the target power and performance/Watt of the RX 7600, the 6 nm node fits the bill, and is cost-effective for the company, giving it headroom for future price-wars against NVIDIA in this segment.

Since it's based on the latest RDNA 3 graphics architecture, the RX 7600 comes with advanced Dual Issue-rate Compute Units with over 17% IPC improvement over the previous RDNA 2 CUs, second generation Ray Accelerators with a claimed 50% increase in ray intersection performance; and for the first time on an AMD GPU, hardware acceleration for AI in the form of two AI Accelerator units per CU. RDNA 3 also introduces hardware-accelerated AV1 video encoding, and the new Radiance Display Engine, with support for the latest DisplayPort 2.1 and HDMI 2.1a ports, and advanced 12-bpc color formats.

AMD intends for the RX 7600 to be seen as a successor to the RX 6600, and not the RX 6600 XT or RX 6650 XT, and so although the Navi 33 silicon has numerically the same number of shaders as the Navi 23 powering the RX 6600 series, there is a numerical increase in shaders for the RX 7600 over the RX 6600, because it maxes out the chip. The Navi 33 features two shader engines, and 32 RDNA 3 compute units, which work out to 2,048 stream processors, 64 AI Accelerators, 32 Ray Accelerators, 128 TMUs, and 64 ROPs. The memory sub-system sees minor updates—the same 8 GB GDDR6 over a 128-bit memory interface, but clocked faster at 18 Gbps, and backed by a faster Infinity Cache memory.

AMD has a reference-design "Made by AMD" (MBA) graphics card design for the Radeon RX 7600, which it intends to sell directly on the AMD website, as well as through its board partners, with minimal re-branding. The company is setting $269 as the baseline MSRP for this card, with board partners expected to come out with overclocked premium non-reference designs.

Radeon RX 7600 Market Segment Analysis
	Price	Cores	ROPs	Core Clock	Boost Clock	Memory Clock	GPU	Transistors	Memory
RX 5500 XT	$170	1408	32	1717 MHz	1845 MHz	1750 MHz	Navi 14	6400M	4 GB, GDDR6, 128-bit
RX 5600 XT	$190	2304	64	1375 MHz	1560 MHz	1500 MHz	Navi 10	10300M	6 GB, GDDR6, 192-bit
RX 6500 XT	$150	1024	32	2685 MHz	2825 MHz	2248 MHz	Navi 24	5400M	4 GB, GDDR6, 64-bit
RTX 2060	$180	1920	48	1365 MHz	1680 MHz	1750 MHz	TU106	10800M	6 GB, GDDR6, 192-bit
RX Vega 64	$320	4096	64	1247 MHz	1546 MHz	953 MHz	Vega 10	12500M	8 GB, HBM2, 2048-bit
RX 5700 XT	$180	2560	64	1605 MHz	1755 MHz	1750 MHz	Navi 10	10300M	8 GB, GDDR6, 256-bit
RTX 3050	$260	2560	32	1552 MHz	1777 MHz	1750 MHz	GA106	12000M	8 GB, GDDR6, 128-bit
RTX 2070	$230	2304	64	1410 MHz	1620 MHz	1750 MHz	TU106	10800M	8 GB, GDDR6, 256-bit
Arc A750	$250	3584	112	2050 MHz	N/A	2000 MHz	ACM-G10	21700M	8 GB, GDDR6, 256-bit
RX 6600	$210	1792	64	2044 MHz	2491 MHz	1750 MHz	Navi 23	11060M	8 GB, GDDR6, 128-bit
RX 6600 XT	$250	2048	64	2359 MHz	2589 MHz	2000 MHz	Navi 23	11060M	8 GB, GDDR6, 128-bit
RTX 3060	$300	3584	48	1320 MHz	1777 MHz	1875 MHz	GA106	12000M	12 GB, GDDR6, 192-bit
RTX 4060	$300	3072	32	1830 MHz	2460 MHz	2125 MHz	AD107	unknown	8 GB, GDDR6, 128-bit
RX 7600	$270	2048	64	2250 MHz	2625 MHz	2250 MHz	Navi 33	13300M	8 GB, GDDR6, 128-bit
Arc A770	$290	4096	128	2100 MHz	N/A	2187 MHz	ACM-G10	21700M	16 GB, GDDR6, 256-bit
RTX 2080	$260	2944	64	1515 MHz	1710 MHz	1750 MHz	TU104	13600M	8 GB, GDDR6, 256-bit
RTX 3060 Ti	$320	4864	80	1410 MHz	1665 MHz	1750 MHz	GA104	17400M	8 GB, GDDR6, 256-bit
RTX 4060 Ti	$400	4352	48	2310 MHz	2535 MHz	2250 MHz	AD106	22900M	8 GB, GDDR6, 128-bit
RX 6700 XT	$320	2560	64	2424 MHz	2581 MHz	2000 MHz	Navi 22	17200M	12 GB, GDDR6, 192-bit
RTX 2080 Ti	$400	4352	88	1350 MHz	1545 MHz	1750 MHz	TU102	18600M	11 GB, GDDR6, 352-bit
RTX 3070	$350	5888	96	1500 MHz	1725 MHz	1750 MHz	GA104	17400M	8 GB, GDDR6, 256-bit
RTX 3070 Ti	$420	6144	96	1575 MHz	1770 MHz	1188 MHz	GA104	17400M	8 GB, GDDR6X, 256-bit
RX 6800	$470	3840	96	1815 MHz	2105 MHz	2000 MHz	Navi 21	26800M	16 GB, GDDR6, 256-bit

Architecture

AMD Radeon RX 7600 is based on the Navi 33 silicon that the company chose to built on the older 6 nm (DUV) foundry node that significantly lower transistor density than the 5 nm EUV node that the Navi 31 powering the RX 7900 series is based on. The chip has a die-area of 204 mm², and transistor count of 13.3 billion (for reference, NVIDIA is able to cram 22.9 billion transistors into a 190 mm² silicon using 5 nm, with the AD106 powering the RTX 4060 Ti). The GPU has essentially the same component hierarchy as the previous-generation Navi 23. Its host interface is PCI-Express 4.0 x8, and power is drawn from a single 8-pin PCIe power connector, which is sufficient, given the gaming total board power for the RX 7600 of 169 W. The GPU features a 128-bit wide GDDR6 memory interface, and 8 GB is the standard memory size for the RX 7600.

AMD hasn't put out a block diagram of the Navi 33, but it features two Shader Engines (compared to six on the Navi 31). Each of these has 8 RDNA 3 Dual-Compute Units (16 CU), which share Raster machinery, and Render Backends. The GPU features Centralized Geometry Processors, asynchronous compute engines, and geometry processors shared among the two Shader Engines. Given its CU count of 32, we arrive at 2,048 stream processors, 32 Ray Accelerators, 64 AI Accelerators, 128 TMUs, and 64 ROPs. The GPU uses a second generation 32 MB Infinity Cache memory that cushions data access to the memory.

Much of the architectural innovation is this generation is with the RDNA 3 Dual-Compute Unit (or Compute Unit pair). The "Navi 33" GPU physically features 32 compute units spread across two Shader Engines. AMD claims that at the same engine clocks, the RDNA 3 CU offers a 17.4% IPC increase over the RDNA 2 CU.

The new RDNA 3 CU introduces multi-precision capability for the 64 stream processors per CU: operating either as 1x SIMD64 or 2x SIMD32 units. The Vector Unit that houses these SIMD units can either function as a SIMD execution mechanism, or as a Matrix execution unit, thanks to the new AI Matrix Accelerator, which provides a 2.7x matrix multiplication performance uplift versus conventional SIMD execution. Also added are support for the Bfloat16 instruction-set, and SIMD8 execution. The GPU hence enjoys AI hardware-acceleration that can be leveraged in future feature-additions relevant to gamers, such as FSR 3.0. Game developers will also look for ways to exploit accelerated AI, now that all three brands feature it (NVIDIA Tensor cores and Intel XMX cores).

AMD's first-generation Ray Accelerator, introduced with the RDNA 2 architecture, was the result of a hasty effort to catch up to NVIDIA with a DirectX 12 Ultimate GPU, where they developed a fixed-function hardware to calculate ray intersections, and offloaded a large chunk of RT processing to the generationally-doubled SIMD resources. With RDNA 3, they've refined the Ray Accelerator to achieve an 80% ray tracing performance uplift over the previous generation, when you add up the Ray Accelerator count, their higher engine clocks, and other hardware-level optimizations, such as early sub-tree culling, specialized box sorting modes, and reduced traversal iterations.

There is a 50% ray intersection capacity improvement for RDNA 3 thanks to these optimizations, and cycles-per-ray reduction. Besides these, AMD has also made several improvements to the geometry- and pixel-pipes, with the introduction of the new multi-draw indirect accelerator (MDIA), which reduces CPU API and driver-level overheads by gathering and parsing of multi-draw command data. At the hardware-level 12 primitives per clock is now supported compared to 8 per clock on RDNA 2, thanks to culling. The core-configuration overall enables 50% more rasterized performance per clock.

AMD has significantly improved the Display Engine of "Navi 33" over the previous-generation in terms of connectivity. The new Radiance Display Engine comes with native support for DisplayPort 2.1, which enables 8K output at up to 165 Hz refresh-rate, or 4K at up to 480 Hz, with a single cable. AMD has refined its FSR 2 algorithm to support 8K (i.e. render at a lower resolution with FSR-enhanced upscaling), to make it possible to enjoy the latest AAA titles at playable frame-rates on 8K displays. The RX 7600 gets two full-size DP 2.1 connectors, besides an HDMI 2.1b, and a USB-C with DP 1.2 passthrough. The "Navi 33" silicon receives full hardware-accelerated AV1 encode and decode capabilities. With this generation, AMD is also introducing SmartAccess Video, a feature that lets the AMD driver leverage the hardware encoders of the RDNA 2 iGPU of Ryzen 7000 desktop processors, for additional encoding performance.

Packaging

The Card

The Radeon RX 7600 follows the design theme established by the company's previous Radeon RX 7000 cards. The main color is black with a few small red highlights. The three red painted cooler fins stand for "3" in RDNA 3—a nice touch. This cooler is all-metal, both the main heatsink and the backplate.

Dimensions of the card are 20.5 x 11.5 cm, and it weighs 758 g.

Installation requires two slots in your system.

Display connectivity includes two standard DisplayPort 2.1 ports (RDNA 2 had 1.4a) and two HDMI 2.1a (same as RDNA 2).

AMD has upgraded their encode/decode setup. It now comes with two independent hardware units that can encode and decode two streams of video in parallel, or one stream at double the FPS rate. There's support for VP9, H.264, H.265 and AV1 decode, and encoding is supported for H.264, H.265 and AV1.

The card uses a single 8-pin power input, rated for 150 W maximum power, plus 75 W over the PCIe slot.

8-Pin won't Connect

When I first installed the RX 7600 I noticed that plugging the power cable in didn't feel 100% right (easy after doing it 10,000+ times in my life). After taking a second look I realized that the PCIe 8-pin didn't go all the way in. It took me a few minutes to figure out that the problem is that the backplate is expanding too far to the PCIe connector area.

Due the way some 6+2 pins are designed they won't fit, because there's a plastic lip that makes contact with the backplate, so the connection can't be made properly. With some other cables in my labs there's no issue—these don't have the raised lip. Roughly 20% of the cables I have here are affected. This is clearly an AMD issue—I've never encountered it on any other card before.

One solution is to remove the backplate and run the card without it, now the plug goes in all the way. Another option is to buy an 8-pin PCIe extension cable without the lip, or try to cut it off from your connector.

Teardown

AMD's thermal solution uses a copper baseplate and two heatpipes to keep the card cool. The main cooler also provides cooling for the memory chips and VRM circuitry.