近期关于AMD、NVIDIA各自下一代游戏卡的传闻越来越多,但都是什么说法都有,有的甚至还互相冲突。

AMD这边的新旗舰卡基于RNDA 2架构,核心代号是Big Navi,或者叫Navi 21,或者叫Sienna Cichild(一种鱼类)。

新卡可能会命名为Radeon RX 6900系列,当然也不排除AMD再次改变命名规则,毕竟这几年A卡名字变得实在是太频繁了。

AMD下代旗舰显卡成谜:GDDR6?HBM?-冯金伟博客园

最新曝料称,Big Navi显卡将搭配2048-bit显存位宽(2×8×128),这样的配置显然只能是HBM系列,而且是两颗显存(每一颗位宽1024-bit),容量可能是2×8GB或者2×16GB,当然后者需要最新的HBM2e,三星、SK海力士均已投入量产。

/* HBM Memory Channel Width */
#define UMC_V8_7_HBM_MEMORY_CHANNEL_WIDTH 128
/* number of umc channel instance with memory map register access */
#define UMC_V8_7_CHANNEL_INSTANCE_NUM 2
/* number of umc instance with memory map register access */
#define UMC_V8_7_UMC_INSTANCE_NUM 8
/* total channel instances in one umc block */
#define UMC_V8_7_TOTAL_CHANNEL_NUM (UMC_V8_7_CHANNEL_INSTANCE_NUM * UMC_V8_7_UMC_INSTANCE_NUM)
/* UMC regiser per channel offset */
#define UMC_V8_7_PER_CHANNEL_OFFSET_SIENNA 0x400

static void gmc_v10_0_set_umc_funcs(struct amdgpu_device *adev)
{switch (adev->asic_type) {
case CHIP_SIENNA_CICHLID:
adev->umc.max_ras_err_cnt_per_query = UMC_V8_7_TOTAL_CHANNEL_NUM;

adev->umc.channel_inst_num = UMC_V8_7_CHANNEL_INSTANCE_NUM;
adev->umc.umc_inst_num = UMC_V8_7_UMC_INSTANCE_NUM;
adev->umc.channel_offs = UMC_V8_7_PER_CHANNEL_OFFSET_SIENNA;
adev->umc.channel_idx_tbl = &umc_v8_7_channel_idx_tbl[0][0];
adev->umc.funcs = &umc_v8_7_funcs;
break;
default:
break;}}

/* HBM Memory Channel Width */
#define UMC_V6_1_HBM_MEMORY_CHANNEL_WIDTH 128
/* number of umc channel instance with memory map register access */
#define UMC_V6_1_CHANNEL_INSTANCE_NUM 4
/* number of umc instance with memory map register access */
#define UMC_V6_1_UMC_INSTANCE_NUM 8
/* total channel instances in one umc block */
#define UMC_V6_1_TOTAL_CHANNEL_NUM (UMC_V6_1_CHANNEL_INSTANCE_NUM * UMC_V6_1_UMC_INSTANCE_NUM)
/* UMC regiser per channel offset */
#define UMC_V6_1_PER_CHANNEL_OFFSET_VG20 0x800
#define UMC_V6_1_PER_CHANNEL_OFFSET_ARCT 0x400

那么,AMD要在高端卡上普及HBM显存吗?也未必。

事实上,AMD至今尚未送出已完工的新显卡PCB电路板方案,显然最终规格也并未定夺,各种可能性都有。

考虑到NVIDIA RTX 30系列已经基本锁定9月份发布,目前正在测试阶段,AMD Big Navi几乎肯定要晚一步到来了。

AMD下代旗舰显卡成谜:GDDR6?HBM?-冯金伟博客园