7.5 GB of usable RAM vs 9 GB of usable RAM, yes they are roughly on par. Let's not forget that the very same games run on PS4pro with only 6 GB of usable RAM as well as PS4 with a mere 5.5 GB.... The only difference is usually the resolution and texture quality. Well a 3 GB of difference between the PS4pro and XBX creates a difference in texture quality but a 1.5 GB will not, but merely resolution differences, which is why I am not so certain that Lockhart can run all XBX games at 4K resolution but will not have a problem running them at 1440p generally speaking.

RDNA 2 is roughly 50%+ faster than Polaris, but of course things vary; however, in the general scheme of things, pretty much 2020 and earlier games should run similarly, if not better, on Lockhart, than in XBX, even if they need to be scaled down to 1440p for one reason or another. In the next-gen compatible titles, however, it will be more performant than XBX due to use of faster RAM, faster SSD, and the utilization of the faster CPU.

Finally, to address some of the suggestions here, the price gap between XBSX will be around $100-$150, depending on what is included in the configuration. If it comes as a digital only console, we might be looking at a $250 4TF 10 GB Lockhart vs fully-fledged $400 XBSX (or for $350 and $500 respectively), which makes even more sense, competing with a regular $500 PS5 and a digital only $450 one, which will then make the competition very interesting between the two. In such a scenario, PS5 will still win in all Asia, and the non-English speaking world, while the English speaking would be home to a fierce competition.

It can't even be compared with the same architectures.

Grab a Radeon 7750 DDR3 and compare it against the Radeon 7750 GDDR5, it's going to have half the performance.
https://www.hardware.fr/focus/76/amd-radeon-hd-7750-ddr3-test-cape-verde-etouffe.html

Grab a Geforce 1030 DDR4 and compare it against the Geforce 1030 GDDR5, it's going to have half the performance.
https://www.gamersnexus.net/hwreviews/3330-gt-1030-ddr4-vs-gt-1030-gddr5-benchmark-worst-graphics-card-2018

Identical GPU's, Identical Architecture, massive differences in capability.

Or take the...
Radeon 7970 @ 3.78 Teraflops.
Radeon RX 470 @ 3.73 Teraflops.

Both Graphics Core Next, Night and day difference...
https://www.anandtech.com/bench/product/1872?vs=1722

Ram is Ram.

The Playstation 4 Pro *could* have shown much larger differences than just resolution/framerate if it wasn't memory constrained... It's a doubling+GST in GPU resources remember. - It was certainly memory constrained. - Could an SSD have mitigated that somewhat? Sure. But it's still not a replacement for lots of fast Ram...
There are plenty of PS4 Pro titles that didn't even get a resolution bump... Or employed a dynamic resolution and often sat around the 1080P mark anyway.

Microsoft saw through this issue and realized that in order to chase higher resolutions with higher quality assets, you needed more memory, hence the upgrade to 12GB.

Lockhart due to it's performance level will be better suited to 1080P.

Actually. RDNA2 isn't 50% faster than RDNA1. AMD has NEVER made that claim.

And RDNA is certainly not faster than Polaris on a per-flops basis... But on a performance per watt basis.

https://www.anandtech.com/bench/product/2525?vs=2578

Essentially a Radeon 5500XT @4.8-5.2 Teraflops is slightly better than a Radeon RX 570 @ 4.8-5.1 Teraflops... Most of the chip has been kept equal too, such as memory bandwidth.

But that is the key thing, it's performance "per watt", not just performance.

And that is entirely expected, RDNA is built on top of the foundations of GCN, uses the exact same instruction set, it's a hybrid GPU design.
https://en.wikipedia.org/wiki/RDNA_(microarchitecture)#Architecture

RDNA2 will take a full architectural deviation from Graphics Core Next. Finally. Yay.

But don't propagate the false claim that it will offer a 50% performance improvement, that is twisting AMD's wording.
https://www.techpowerup.com/264538/amd-rdna2-graphics-architecture-detailed-offers-50-perf-per-watt-over-rdna

I won't personally speculate on price, because there hasn't been any real concrete evidence on the various price points manufacturers are gunning for... Or how that will translate to certain market success/failures.

That is entirely possible, just enough storage for the OS+Future updates and a reliance on expandable storage.

I never said that AMD said that RDNA2 is 50% faster than RDNA, no, I said RDNA2 is 50%+ faster than Polaris, and this is not a claim made by AMD but others out there like Mark Cerny (literally said this in his presentation a couple of months back) and MANY PC reviewers in their benchmarks. If you search around, you will see that this is indeed the case. Even RDNA cards are much faster than Polaris, TFlops to TFlops.

A simple but popular comparison:
https://www.eurogamer.net/articles/digitalfoundry-2019-teraflop-face-off-current-gen-vs-next-gen

Also one example you have shown between DDR3 vs GDDR5 is very interesting and finds an average difference of 36% performance deficit with DDR3 (15% to 54%), which reminds me of the situation between XB1 and PS4 if it weren't for the ESRAM. However, the memory bandwidth difference between the XBX and the Lockhart would be relatively small and it will be mostly down to the architectural differences, as well as CPU and Disc bottlenecks.

No doubt Series S (by the rumor) is stronger than XSX and surely also cheaper than to produce than it. Games will probably be on similar disparity to Series X than X1 is against X1X.

Nickname succesfully created.

I have joined the discussion late...but I just ordered an Xbox One X on Amazon ( as I will get a PS5 in holidays but want to play Halo Infinite) and looking at the Lockhart's leaked specs...I feel good in my purchase until I can upgrade to a series X a few years from now.

Lockhart should outperform XB1 X in pretty much every area, with the one possible exception being texture quality, since XB1 X has more RAM and can throughput larger texture files as a result, but Lockhart may be able to win there as well using texture streaming from the SSD. Lockhart GPU should outperform XB1 X by a fair margin in spite of the lower tflop rating, while CPU and storage will be far, far better on Lockhart.

I don't think anything is wrong with your purchase decision since XBX is the best way to play 3rd party games, we are still 6 months away from the release of the next-gen consoles, which are definitely going to be more expensive than XBX. Also Lockhart is not even announced yet so who knows when it will be released. Additionally, MS openly said that there will be no XBSX exclusives for the first two years (so you are not losing much for at least 2.5 years). Basically if you want an Xbox machine now, XBX is the more reasonable option.

However, with that said, the Jaguar cpu cores, the lack of an SSD, as well as the new GPU feature set will start to give some sub-par performance on the XBX, which I don't think will be too big of deal-breaker for now. You can always resell you XBX for half the price and buy a next-gen XBSX or Lockhart anyways. I have recently bought a PS3 for around $100, fully modded, and I do not regret it a bit.

That 7.5 GB of RAM makes no sense. Devs can do a lot when it comes optimising their software for lower spec-ed SKU, but there are few areas, where the optimisation could be impossible or at least unsustainable, and RAM is one of them. If that's true, it could mean bigger fragmentation (if MS ever allows it), higher developing cost, performance issues and delays. It could work for them, but only if Lockhart becomes very successful. However, that'd also mean that MS puts all their eggs in one basket, and it could bite them in their ass later on, especially if there are no spec differences between both PS5 SKUs.

I don't think Series S will be inferior to X1X even on texture quality. Even if it have less RAM, but if the bandwidth is kept similar to Series X and with SSD being faster to fill the RAM then it will need to keep less info on the RAM compared to X (see Mark Cerny GDC presentation) then it will be able to have more relevant data on the RAM and overcome the gap.