AMD 9800X3D Has an Unlocked Multiplier According to Leaked Specs and a New Rumor Suggests That Its 3D V-Cache Is Layered Under the CCD

Yes the 3d vcache being below the main compute to allow clocks to not be throttled down is very interesting. I wonder if it impacts mounting pressure tolerances. Especially for those that delid.
 
Yes the 3d vcache being below the main compute to allow clocks to not be throttled down is very interesting. I wonder if it impacts mounting pressure tolerances. Especially for those that delid.
Could be better, could be worse, right?

I'd hope for better (safer) personally :)
 
As mentioned in the other thread, there were serious hints that changes to the 3d Vcache were coming (combination of Zen5 chip layout making old layout unworkable, TSV (chip interconnect) mount points looking radically different in Zen5, and the fact that every leak about Zen5 X3D parts suggesting drastically improved performance over Zen4 X3D, despite regular Zen5 only having very minor performance improvements over regular Zen4, suggesting a large clock speed increase was coming.

I had guessed some new heat spreader design was incoming, but if these rumors are true, the actual solution is a big "duh" moment.

The old X3D design with the 3D Vcache on top made no sense at all. The Cache chips generated comparatively very little heat, whereas the main core (integer/FPU) silicon has very bursty high heat loads. It made no sense to bury the hottest part on the bottom further away from the cooler, and have the cool part near the top.

In my mind I'm picturing a meeting where some new guy (or gal) to the team raises his hand in a meeting about the issue of heat dissipation in stacked designs and is like "why don't we just switch the order, putting the hot one on top, and the cool one on the bottom?" followed by everyone smacking themselves on their foreheads wondering why they didn't think of that two generations ago.

I hope that person got a promotion :p
 
I'd assume that the 'hat' position was the easiest (safest?) to implement electrically / mechanically; it's a risky thing to do from a yields perspective I'd think.

Moving it to the bottom, then, is more a refinement that lets AMD sell higher-clocked stacked CPUs. Keeping in mind that these dies are going to Epyc SKUs first, there likely had to have been a market for such products for enterprises to make this change happen.

Not that I'm complaining!
 
Keeping in mind that these dies are going to Epyc SKUs first, there likely had to have been a market for such products for enterprises to make this change happen.

Yeah, AMD has sold Epyc "X" SKU's with up to 800MB of total cache since Zen2/Milan.

 
Well, only 2 weeks until they're out in the wild and we'll get to see real reviews. Can't wait but even doesn't matter if I want this or a 9900/9950X3D since there are no mATX boards out yet for the 800 series. I'd really like to get an 870 mATX but ASUS has a nice ITX already out.
 
Well, only 2 weeks until they're out in the wild and we'll get to see real reviews. Can't wait but even doesn't matter if I want this or a 9900/9950X3D since there are no mATX boards out yet for the 800 series. I'd really like to get an 870 mATX but ASUS has a nice ITX already out.

Aren't the differences between the 800 series and 600 series chipsets mostly academic?

I vaguely remember reading that the only difference was that the added a 40Gb/s USB requirement?

Maybe I am not remembering that right, but it was something like that.

I remember reading that pretty much everyone had the take that X870E wasnt ready for the AM5 launch, but that didn't matter because X670E was pretty much identical apart from the 40Gbps USB requirement.
 
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I remember reading that pretty much everyone had the take that X870E wasnt ready for the AM5 launch, but that didn't matter because X670E was pretty much identical apart from the 40Gbps USB requirement.
The Realtek USB4 chipset that they're using now wasn't ready; those that had USB4 or TB4 were using the Intel chipset for the 600-series boards.
 
Aren't the differences between the 800 series and 600 series chipsets mostly academic?
Pretty much. USB4 and PCIe 5.0 for the GPU. Currently not a big deal but this is likely going to be a rig I'll be using going into retirement (6 years on the horizon) so making a solid choice now will have long term positives down the road.
 
So who has any experience with these mobo's that you can flash without CPU installed? If I go the 9800X3D route I need to get it working too.

Atm mostly leaning rowards Gigabyte > Asus > Asrock/MSI but Gigabyte's seems spotty at best.
 
So who has any experience with these mobo's that you can flash without CPU installed? If I go the 9800X3D route I need to get it working too.

Atm mostly leaning rowards Gigabyte > Asus > Asrock/MSI but Gigabyte's seems spotty at best.
Is that possible? Interesting. I know AMD used to ship out a bios upgrade kit if you requested but that was a while back
 
Is that possible? Interesting. I know AMD used to ship out a bios upgrade kit if you requested but that was a while back

More premium motherboards have had this for a long time.

The actual steps to make it work vary, but usually you have to format a USB stick a particular way, and put the intended bios update on it in the exact location, with the exact filename specified in the instructions, and then stick the USB stick in the exact USB port the manual tells you to, and then you fire it up.

I can't remember how you know when it is done. Maybe some LED indicators on the motherboard? I havent done this in a long time.
 
So who has any experience with these mobo's that you can flash without CPU installed? If I go the 9800X3D route I need to get it working too.

Atm mostly leaning rowards Gigabyte > Asus > Asrock/MSI but Gigabyte's seems spotty at best.

Is that possible? Interesting. I know AMD used to ship out a bios upgrade kit if you requested but that was a while back
More premium motherboards have had this for a long time.

The actual steps to make it work vary, but usually you have to format a USB stick a particular way, and put the intended bios update on it in the exact location, with the exact filename specified in the instructions, and then stick the USB stick in the exact USB port the manual tells you to, and then you fire it up.

I can't remember how you know when it is done. Maybe some LED indicators on the motherboard? I havent done this in a long time.

Here is the Asus page on the topic, but each manufacturer will differ.

Here is what the manual says for my Asus ROG Zenith II Extreme Alpha:

1730407106304.png

As for which one to buy, I have no idea. I have very clear memories of doing this once, but I can't for the life of me remember where or when, what system it might have been on or what motherboard it may have used.

I would definitely download the manual for the board you are considering and read it before buying, as it is hit or miss which boards support this.

I think it is slightly expensive to add it, as they need to add a secondary small embedded CPU to the board to handle the flash process. These tiny embedded CPU's are not expensive, but costs add up, so at least traditionally these things have only been offered on Server and Workstation boards that have IPMI/BMC and very high end consumer boards.
 
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I think it is slightly expensive to add it, as they need to add a secondary small embedded CPU to the board to handle the flash process. These tiny embedded CPU's are not expensive, but costs add up, so at least traditionally these things have only been offered on Server and Workstation boards that have IPMI/BMC and very high end consumer boards.

From what I have seen, quite a nr of X870 boards seem to have the functionality, alas, a lot of the boards also seem to lack the amount of M2 and SATA ports I would like to use unless I want to run my GPU at 8x and disable other PCIe slots on the mobo which my soundcard needs.

X670 boards seem to be a bit better in this regard, not sure why, maybe they needed to sacrifice for the USB4 functionality?
 
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