Intel doesn't have a uarch problem, they have a fab problem. They need to decide - and quickly - if they are capable of keeping up with TSMC or even Samsung, and if not, they need to at the very least start dual sourcing.
It is kind of both. My assumption is that all of Intel’s designs were monolithic until AMD shook up the market. The lead time for a completely new design is very long, so I expect that their cpus, regardless of process tech, will be monolithic up until 2022. They are leaking all kinds of stuff to try to keep people interested, but they just don’t have competition for quite a few AMD parts. They have talked about their chip stacking tech, which was probably started quite a while ago, but that was probably for very low power mobile parts. Chip stacking is the norm in cell phone processors and such.
The shortage of 14 nm part indicates a lot of accelerated, cancelled, and changed plans inside intel. I kind of wonder if it is partially due to suddenly needing to make a huge number of 8 core parts on 14 nm when they never intended to do so. We should have had 8 core parts for the high end on 20 nm. AMD (technically) did it on 28 nm with excavator based parts, but they had shared FPUs. Integer ALUs are tiny, but FPUs are comparatively huge. Intel just kept on selling 4 core parts because they could, even though 8 core should have been mainstream at 14 nm. Now they have to make all of these 8 core parts that would have been high priced Xeons or HEDT parts before.
When they finally get a 10 nm or below part out, it is probably going to be a monolithic 10 core part. That isn’t going to compete well with AMD’s chiplet based parts that will be much cheaper to produce. Also, I think intel will have a very tough time competing with their own 14 nm parts. They will probably have lower performance for gaming compared to high clocked 14 nm parts. I find the gaming performance thing kind of ridiculous anyway, since it is mostly at low quality and at ridiculously high FPS for all processors. It would be bad PR to lose to their own older cpus and possibly to AMD’s parts , even if it isn’t a particularly valid use case. The rumored back port of a 10 nm design to 14 nm ++(+?) May allow them to compete in the desktop market with Zen 2, although Zen 3 may change that. They will take a lot more power even if they win some performance benchmarks. They may also have trouble meeting demand due to the large die size on 14 nm. If it was planned for 10 nm, then it will be huge and power hungry on 14 nm variant. They could get closer feature parity by supporting pci-e 4.0 though.
The server landscape is even worse, although intel has the advantage that a lot of systems are planned significantly in advance, so even if AMD is better in almost every way, they will continue to sell server processors for years. The server market is very conservative. They will not switch easily. Intel isn’t going to be competitive with their monolithic designs and a design actually optimized for a chiplet architecture will take years of work. They tried with the Xeon platinum 9200, but that is a marketing stunt really. No one will buy that part. It is 2 almost 700 square mm die, so it will be ridiculously expensive. Even if it wasn’t ridiculously expensive, it is still more than 2x the power of a competing AMD part which doesn’t work for big server installations.
One thing to keep in mind is that TSMC has good reason to support AMD strongly. Intel has their own fab so they are technically competition to TSMC. TSMC can’t get a part of the massive AMD64 server market except by supporting AMD or through ARM processor overtaking the AMD64 market. They probably get a small part for the revenue through accessory chips, but they would get that anyway. Intel had, I believe, close to 99% of the server market share. With AMD now taking a chunk of that, TSMC also gets a part of that. Without AMD they were almost completely locked out. There has been some move by big vendors to just make their own chips, so ARM could be a big factor also going forward. I don’t know how the current ARM server chips compare to Epyc though.
So I think intel does have a uarch problem, depending on what you consider part of the uarch. While their mesh network L3 cache does provide a monolithic last level cache, it seems quite expensive to do so. The power consumption on chips with the mesh network were higher than expected and higher than Intel’s ratings would indicate. The mesh network may not be that worthwhile for 8 cores or less and it can’t work across multiple chiplets. The power consumption would go through the roof unless they are split off into separate NUMa nodes, which means it isn’t a monolithic last level cache any more. While intel will have a response eventually, it is actually unclear whether they can pull ahead. They aren’t going to have the process tech advantage anymore like they did compared to AMD’s fab. TSMC represents a massive portion of the entire market, so they have the resources to push the process tech. As far as design, it is also unclear whether they can pull ahead. We now have many companies with the expertise to design high performance cpus.
A lot of customers also realize how bad it is to have a single supplier. The cloud computing companies took a big hit with spectre, meltdown, etc. They will want to have some diversity such that their entire business isn’t shutdown by some vulnerability from one supplier. That is good for AMD, but may also be good for ARM based solutions. The next few years will be interesting. As a customer, I hope intel and nvidia get some good competition. It isn’t in the consumers best interest to have a single dominant company.