AMD’s Radeon RX 6400 and RX 6500 XT should appeal to gamers with a smaller budget. The RX 6500 XT has a suggested retail price of $ 199 [-] Then there are taxes and the completely different price structure these days. It is therefore unclear whether economical raytracing-capable cards with modern RDNA2 architecture and current display connections will actually be available for less than 250 euros in the end.
In any case, AMD is making an effort to prevent crypto miners from buying the 6500 XT and the 6400 – if you want to see the extremely narrow memory interface with only 64 bits as positive. The same graphics chip used in the notebook shows that it actually has a 128-bit wide interface. The Infinity cache, memory bandwidth saver in an emergency, is also very tight with only 16 MB. Crypto miners are held responsible for the shortage of graphics cards and, as a result, the high prices, but they require a high memory bandwidth and, above all, more than 4 GB of memory to calculate the hash values of the crypto currency Ethereum [-] the 6500/6400 only have 4. This makes the restriction to a 64-bit interface all the more incomprehensible.
According to its own performance measurements, AMD wants to leave the widespread, but already older, Radeon RX 570 and Nvidia’s GeForce GTX 1650 well behind in games in Full HD resolution at a high level of detail. In-house benchmarks from AMD certify that the product has a lead of up to 60 percent over the GTX 1650 in the horror shooter Resident Evil: Village. Mostly it is more like 30 percent [-] a difference that you can feel when switching.
(Image: AMD)
In the market, it will also have to assert itself against Nvidia’s newly introduced GeForce RTX 3050, which is likely to be more expensive [-] you can read a test in one of the upcoming issues of c’t.
New, small sat nav
The heart and mind of the Radeon RX 6500 XT, of which there will most likely not be a reference design, is a new graphics chip, the Navi24. It is manufactured at TSMC using 6 nanometer technology and contains 5.4 billion transistors.
The chip controls two displays via DisplayPort 1.4c DSC and HDMI 2.1 with a variable refresh rate, but its video units to relieve the CPU are slimmed down. Decoding is possible in the formats H.264, H.265 / HEVC, the AV1 decoder of the Radeon RX 6600 has been deleted. The encoding is also ebb: The Navi24 is not allowed to accelerate any of the modern formats on the Radeon RX 6400/6500 XT.
Speaking of accelerating: When it comes to clock speeds, the Radeon RX 6500 XT with its 1024 shader processing cores in 16 compute units is well ahead and reaches up to 2815 MHz, typically around 2610 MHz in games. It thus creates a nominal throughput of just under 5.8 TFlops, for which 144 GByte / s of storage transfer rate are available. The maximum power consumption should be 107 watts, a 400 watt power supply is sufficient.
The Radeon RX 6400 is significantly more economical with only 53 watts, should also get by with single-slot cooling and does not need an extra connection for power from the power supply. On the other hand, with 768 shader cores, i.e. 12 compute units, at 2039 MHz (3.6 TFlops) and slower GDDR6 memory (128 GByte / s), it is significantly weaker. So far, there is no concrete performance information about her.
(csp)