AMD Radeon R9 390X vs AMD Radeon Instinct MI455X
GPU Specs Compare
Graphics Card
Release Date
Jun 2015
Jul 2026
Generation
Pirate Islands
Radeon Instinct
Type
Desktop
Desktop
Bus Interface
PCIe 3.0 x16
PCIe 6.0 x16
Clock Speeds
Memory Clock
1500 MHz
1900 MHz
Base Clock
-
1000 MHz
Boost Clock
-
2400 MHz
Memory
Memory Size
8GB
432GB
Memory Type
GDDR5
HBM4
Memory Bus
512bit
24576bit
Bandwidth
384.0GB/s
23.3TB/s
Render Config
Compute Units
44
256
Shading Units
2816
32768
TMUs
176
1024
ROPs
64
0
L1 Cache
16 KB (per CU)
32 KB (per CU)
L2 Cache
1024 KB
192 MB
Theoretical Performance
Pixel Rate
67.20 GPixel/s
0 MPixel/s
Texture Rate
184.8 GTexel/s
2457.6 GTexel/s
FP32 (float)
5.914 TFLOPS
157.3 TFLOPS
FP64 (double)
739.2 GFLOPS
2.458 TFLOPS
FP16 (half)
-
157.3 TFLOPS
Graphics Processor
GPU Name
Grenada
MI450 256CU
GPU Variant
Grenada XT(215-0880004)
-
Architecture
GCN 2.0
CDNA 5.0
Foundry
TSMC
TSMC
Process Size
28 nm
2 nm
Transistors
6.2 billion
320 billion
Die Size
438 mm²
Unknown
Board Design
TDP
275W
2300W
Suggested PSU
600 W
2700 W
Outputs
2x DVI1x HDMI 1.4a1x DisplayPort 1.2
No outputs
Power Connectors
1x 6-pin + 1x 8-pin
None
Graphics Features
DirectX
12 (12_0)
N/A
OpenGL
4.6
N/A
OpenCL
2.0
3.0
Vulkan
1.2
N/A
Shader Model
6.3
N/A