Did you know that the RTX 4070 was originally designed with only 10GB of VRAM? So the rumors say, and Harukaze5719 on X (Twitter) discovered one of these ultra-rare Nvidia RTX 4070 10GB prototypes, which used the AD104-275 chip and had a 160-bit memory interface.
The RTX 4070 that was finally released has 12GB of GDDR6X memory on a 192-bit interface and is among the best graphics cards around.
Prior to the debut of the RTX 40 series, leaks suggested that Nvidia intended to build the next-gen RTX 4070 with just 10GB of VRAM. These leaks were perhaps true, or at least Nvidia considered these specs, as there is now evidence that pre-production samples of the Nvidia RTX 4070 10GB were actually built.
A prototype Nvidia RTX 4070 10GB, seen in GPU-Z
O GPU-Z screenshot of the 4070 prototype specs reveals how Nvidia created this original variant of the graphics card. Nvidia reduced the memory width to just 160 bits, with five 2GB memory chips offering a total capacity of 10GB. This was achieved by disabling one of the six 32-bit memory controllers on the AD104 chip. As a result, bandwidth and memory capacity were limited, giving the 10GB prototype 4070 only 420GB/s of memory bandwidth, 16.7% less than the RTX 4070 video card released in April 2023.
Interestingly, Nvidia was apparently hoping to compensate for the reduced VRAM and bandwidth by giving the GPU more CUDA cores. The prototype RTX 4070 has 7,168 CUDA cores, 1,280 more than the standard version of the RTX 4070, and the same number as the RTX 4070 Super. The prototype also has an eight-slot PCB for soldered memories, presumably using a modified version of an AD103 (RTX 4080) board.
Although this Nvidia RTX 4070 10GB prototype had noticeably more CUDA cores than the stock version, the memory subsystem would have been problematic. It was also rumored to have slower GDDR6 memory instead of GDDR6X, although there are no clues as to the size of the L2 cache; a larger cache might have mitigated some of the bandwidth impacts, notes Tom’s Hardware.
What is the minimum amount of VRAM today?
The RTX 3080 10GB was the perfect candidate for testing the capabilities of 10GB VRAM in modern titles. 10GB of VRAM, on Nvidia GPUs in particular, has been found to show noticeable limitations in the latest titles. Horizon Forbidden West is a prime example where 10GB starts to show the same limitations as 8GB GPUs. In this game, at 1080p and 1440p, the RTX 3080 10GB does well, but completely falls apart at 4K, where 11GB of VRAM is required to run the game smoothly at maximum settings, according to Tom’s Hardware.
12GB of VRAM is now the minimum amount of VRAM that modern titles realistically require (with one or two exceptions) to run at maximum settings, and it’s good that Nvidia has changed its mind to reflect this reality in terms of graphics card RTX 4070.
If the company had gone the less VRAM route, 4070 users would have been in a similar situation to RTX 3060 Ti, 3070 and 3070 Ti users who have been experiencing memory capacity issues for years due to that Nvidia only gave these GPUs 8GB of memory.
Source: www.go4it.ro
