DDR5 as Vram

[Asni]

Hi, i noticed that GPU-Z cannot read DDR5 properly: as a result, the software reports double the real bandwidth.
This happens on any platform supporting DDR5, both Intel and Amd, with an iGPU.

I supposed this is due to the new architecture which takes advantage of a dual subchannels system (2x32bit*) instead of a single 64bit* bus like before. This helps signal integrity and efficiency but it doesn't increase bandwidth.

*Without ECC bits.

 

[TumbleGeorge]

Hi, i noticed that GPU-Z cannot read DDR5 properly: as a result, the software reports double the real bandwidth

I didn't see that in your screenshots? It's normal.

 

[Asni]

I didn't see that in your screenshots? It's normal.

It's not.

3200Mhz-->6400MT/s (Double Data Rate) in a dual channel configuration lead to 102.4GB/s while the software reports 204.8GB/s.
You can do the math: 6400/8*2*64 or 6400/8*2*2*32 considering the dual subchannels configuration. Still 102.4GB/s.

And so on:
3000Mhz-->6000MT/s 96GB/s
3467Mhz-->6934MT/s 110.94GB/s
3400Mhz-->6800MT/s 108.8GB/s

 

[Wirko]

Maybe that's because GDDR has QDR data transfer (at least some types, and also depending on which clock signal you take as reference). So GPU-Z could assume it's QDR when it isn't.

 

[TumbleGeorge]

Hmm, i see this row after OP guide. Yes there have problem.