ATI Radeon HD 4870 Mac Edition

Benchmark Performance

The ATI Radeon HD 4870 Mac Edition occupies a firmly mid-pack position in the overall GPU landscape, landing at the 50th percentile among all GPUs in the benchmark database. This places it exactly at the median of tracked graphics hardware — a card that delivers competent, if not spectacular, performance for its era. The data shows a card built around the RV770 chip on AMD's TeraScale architecture, with 800 shading units, 40 texture mapping units, and 16 raster operation pipelines driving a peak FP32 throughput of 1,200.0 GFLOPS.

With no direct rival scores provided in the nearestRivals field, the percentile ranking serves as the primary comparative anchor. Being at the 50th percentile means half of all GPUs in the database outperform it, and half underperform it. This is a classic mainstream-to-upper-midrange positioning — not a halo product, but far from an entry-level part. The pixel fill rate of 12.00 GPixel/s and texture fill rate of 30.00 GTexel/s are consistent with a card designed for 1080p-class gaming in its generation, though the 512 MB memory capacity would prove limiting at higher resolutions.

The architecture's TeraScale design, built on a 55 nm process at TSMC, houses 956 million transistors across a 256 mm² die, yielding a transistor density of 3.7 million transistors per square millimeter. These figures indicate a moderately complex chip for its time — smaller and denser than the preceding Radeon R600 architecture, which it directly succeeded. The performance characteristics align with the R700 generation (HD 4800 series) positioning, where the focus was on throughput per dollar rather than absolute flagship dominance.

Benchmark results indicate the card's compute capabilities are balanced between pixel and texture work, with the 1,200 GFLOPS FP32 figure suggesting competent shader performance for DirectX 10.1 workloads. The 50th percentile standing means users upgrading from integrated graphics or older discrete cards would notice substantial gains, while those accustomed to high-end modern GPUs would find the performance underwhelming. In the absence of specific rival deltas, the percentile data alone tells a story of a card that was respectably mid-range at launch and has since been surpassed by the march of generations, culminating in its end-of-life production status.

Power and Cooling

The ATI Radeon HD 4870 Mac Edition carries a thermal design power of 150 W, which places it in a moderate power-consumption tier for its generation. The data indicates a recommended power supply of 450 W, meaning system builders should ensure their PSU meets this threshold before installation. The card requires two 6-pin power connectors, a dual-connector setup that was standard for performance-oriented GPUs of this era.

Cooling is handled by a dual-slot design, which provides adequate surface area for heat dissipation given the 150 W TDP. The physical dimensions extend to 250 mm in length (9.8 inches), so case compatibility should be verified — particularly in compact or legacy Mac Pro chassis where space may be constrained. The dual-slot form factor means the card occupies two expansion slots, which is typical for cards with this power envelope and cooling requirements.

The 55 nm manufacturing process influences power efficiency characteristics; while not as efficient as later smaller-node parts, the 150 W figure is manageable for a 450 W PSU. Users should note that the two 6-pin connectors must both be populated for the card to function correctly — power draw at full load will approach the TDP limit, and insufficient connector supply from the PSU could cause instability. The suggested 450 W PSU provides a reasonable headroom margin above the card's TDP, accounting for other system components drawing power from the same supply.

Who Should Consider It

The Radeon HD 4870 Mac Edition's 50th percentile performance ranking makes it suitable for specific use cases, primarily legacy gaming and Mac-centric workflows from its 2009 release era. Given that the card's average benchmark score is recorded as 0 in the database — indicating no active benchmark submissions — the practical performance assessment relies on the percentile placement and architectural specifications rather than direct measured scores.

At 1080p resolution, the card's 800 shading units and 12.00 GPixel/s pixel rate could handle older DirectX 10.1 titles at medium to high settings, provided texture memory demands stay within the 512 MB VRAM limit. The 108.8 GB/s memory bandwidth helps mitigate the small frame buffer somewhat, but games exceeding 512 MB of texture data would force asset streaming or reduced quality settings. For 1440p or higher resolutions, the 512 MB capacity becomes a hard bottleneck — the card simply does not have enough onboard memory to hold modern scene data, leading to stuttering or texture pop-in.

This card is best suited for users running legacy software that predates its release, or for those building a period-appropriate system where this GPU was the intended performance tier. It is not recommended for contemporary gaming at high resolutions, nor for compute workloads requiring modern API support, as the card lacks Vulkan support entirely and tops out at DirectX 10.1 and OpenGL 3.3. Mac users with compatible systems from that era, specifically those needing a PCIe 2.0 x16 card with the Mac Edition's specific output configuration, would be the primary audience — though the end-of-life production status means availability is limited to used markets.

FAQ

Q: What is the memory configuration of the ATI Radeon HD 4870 Mac Edition?

A: The card features 512 MB of GDDR5 memory on a 256-bit bus, delivering a bandwidth of 108.8 GB/s with an effective memory clock of 3.4 Gbps.

Q: Does this GPU support modern graphics APIs?

A: No. The card supports DirectX 10.1 (10_1) and OpenGL 3.3, but has no Vulkan support, making it incompatible with modern Vulkan-based games and applications.

Q: What power supply is required for this card?

A: The suggested PSU rating is 450 W, and the card requires two 6-pin power connectors to be populated. The TDP is rated at 150 W.

Q: What display outputs are available on the Mac Edition?

A: The card provides one DVI port and one mini-DisplayPort 1.0 output, supporting dual-display configurations.

Q: What is the production status of this GPU?

A: The ATI Radeon HD 4870 Mac Edition is end-of-life, meaning it is no longer manufactured and is only available through secondhand channels.

Q: What architecture is this card based on?

A: It uses the RV770 chip with AMD's TeraScale architecture, fabricated on a 55 nm process at TSMC, with 956 million transistors on a 256 mm² die.

Ray Tracing and Feature Set

The ATI Radeon HD 4870 Mac Edition predates ray tracing acceleration entirely. The data shows no ray tracing cores and no tensor cores, confirming this GPU has no hardware support for ray-traced rendering or AI-accelerated features. This is a pure rasterization card from the TeraScale era, where rendering was done through the traditional shader pipeline.

The feature set is defined by its API support: DirectX 10.1 with shader model 10_1, OpenGL 3.3, and no Vulkan. This means the card can run DirectX 10 and 10.1 titles natively, along with OpenGL applications up to version 3.3. It cannot run DirectX 11 or later games, nor Vulkan titles, which effectively limits its software compatibility to games and applications from approximately 2007-2010. The absence of modern feature support is a critical limitation for any contemporary use case.

The 800 shading units handle all compute and graphics workloads through the TeraScale architecture's unified shader design. The 40 texture mapping units and 16 ROPs provide the fixed-function throughput necessary for texture filtering and pixel output. The card's feature set was competitive for its 2009 release window, but the lack of forward-looking API support means it cannot leverage any modern rendering techniques, including hardware-accelerated ray tracing, variable rate shading, or mesh shaders.

Memory Subsystem

The memory subsystem is a defining characteristic of the Radeon HD 4870 Mac Edition, combining a modest 512 MB capacity with high-bandwidth GDDR5 technology. The 256-bit memory bus runs at 850 MHz, translating to an effective data rate of 3.4 Gbps and yielding a total bandwidth of 108.8 GB/s. This bandwidth figure is respectable for the era and helps compensate for the relatively small frame buffer.

For high-resolution gaming, the 512 MB capacity poses a significant constraint. Modern games at 1080p typically require 2-4 GB of VRAM for high-quality textures, and even games from the card's era could exceed 512 MB at higher resolutions and quality settings. When VRAM capacity is exhausted, the card must fall back to system memory over the PCIe 2.0 x16 interface, which causes severe performance degradation due to the far lower bandwidth available over the bus compared to the dedicated GDDR5.

The 108.8 GB/s bandwidth is well-matched to the 1,200 GFLOPS compute throughput, ensuring that shader units are not starved for data in most workloads. However, the 256-bit bus width and 512 MB capacity represent a deliberate design choice to balance cost and performance — the bandwidth is sufficient for the chip's compute capabilities, but the capacity limits the card's ability to handle large texture sets or high-resolution render targets. For the Mac Edition specifically, the mini-DisplayPort 1.0 output supports modern displays, but the memory subsystem will bottleneck any attempt to drive high-resolution monitors in graphically intensive applications.

How It Compares

The nearestRivals data for this GPU is empty, meaning no direct competitor comparisons with specific scores and delta percentages are available in the database. This absence of rival data requires the analysis to rely on the 50th percentile ranking and architectural positioning relative to its known predecessors and successors.

Predecessor — Radeon R600: The HD 4870 Mac Edition represents a significant architectural advancement over the R600 series. The R700 generation moved to a denser 55 nm process and introduced GDDR5 memory support, which the R600 lacked. The 800 shading units in the HD 4870 double the shader count of many R600 parts, and the 108.8 GB/s bandwidth substantially exceeds R600's capabilities. The percentile ranking shows the HD 4870 holding the median position, whereas R600 parts would likely fall below that threshold given their older architecture and lower performance ceilings.

Successor — Evergreen: The Evergreen generation succeeded the HD 4800 series and pushed the architecture forward with support for DirectX 11, a feature the HD 4870 cannot offer. Evergreen parts generally moved to smaller process nodes and larger memory configurations, addressing the key limitations of the HD 4870's 512 MB frame buffer and DirectX 10.1-only API support. The HD 4870's 50th percentile ranking would be lower relative to Evergreen parts, which benefit from architectural improvements and broader software compatibility.

Market Position: Without specific rival scores, the 50th percentile placement is the only quantitative comparison available. This ranking indicates that the HD 4870 Mac Edition sits at the exact midpoint of all GPUs in the database — a position that reflects its status as a competent mid-range card from a bygone era, outclassed by newer generations but historically significant as a bridge between the R600 architecture and the Evergreen line that followed.