SC104 — 128-Core CFD HPC Node with 512 MB Cache and 12-Channel Memory for ANSYS Fluent

The SC104 node is the largest configuration in the lineup. It runs a single AMD EPYC 9755 — 128 cores and 256 threads, all of them at 4.1 GHz — with 512 MB of L3 cache and twelve DDR5 memory channels behind it. Paired with 128 GB of RAM and 2 × 1.88 TB NVMe SSD, it puts what would otherwise be a small cluster's worth of cores into a single socket, with no network between ranks.

One notable detail: on this chip, AMD's boost clock and all-core boost are the same 4.1 GHz. There's no drop-off when every core is loaded — all 128 run at the same speed under a full parallel job as a single core does on its own.

Specifications

512 MB of L3 is the largest cache here by a wide margin, and 4.1 GHz across all 128 cores matches the all-core clock of our 48- and 96-core tiers — so the extra cores don't come at a clock penalty. Twelve memory channels deliver roughly 600 GB/s.

Sizing note: read this before choosing SC104

SC104 carries 128 GB of RAM across 128 cores — about 1 GB per core, the tightest ratio in the lineup. Memory bandwidth is also the same 600 GB/s shared by twice as many cores as our 64-core node. Both facts point the same way: this node's strength is running many jobs at once, not one job as fast as possible.

For a single Fluent case, 128 MPI ranks is beyond where most CFD problems scale usefully. As a rough guide, Fluent needs about 1 GB of RAM per million cells for a typical steady single-phase case, so a mesh fitting in 128 GB gives each of 128 ranks a very small share of cells — at which point boundary-data exchange between ranks starts to outweigh the solving work, and a 24- or 32-core node will often finish the same case sooner.

Where SC104 genuinely wins is concurrency: eight cases on 16 cores each, four on 32, or a large DOE sweep run in parallel batches. Total throughput per hour on this node is unmatched — it's the distribution of that throughput that differs from the smaller tiers.

If you have one very large case rather than many, talk to us first. Depending on the mesh, a 32- or 64-core tier may solve it faster, and we'd rather tell you that than rent you 128 cores your case can't use.

What this node is built for

SC104 is the maximum-capacity throughput tier. It suits:

• Running many cases concurrently — the clearest use of 128 cores: a full DOE sweep, a mesh-independence study, or a batch of design variants, several at a time on partitioned core groups.

• Teams sharing one node — several engineers running their own cases simultaneously without queuing behind each other.

• Very large cases that genuinely scale past 96 ranks — rare, but when you have one, this is the node for it.

• Time-critical batch work — when a week of sequential runs needs to compress into a day.

• Cluster-scale parallelism without a cluster — 128 ranks on one socket, no network hop, no MPI-over-network tuning.

• Heavy I/O batch runs — NVMe storage handles many concurrent jobs writing data files and autosaves.

Choosing SC104

Choose SC104 when:

• You have many cases to run rather than one, or

• You have a genuinely enormous case that has been shown to scale past 96 ranks, and it fits within 128 GB.

For a single moderate case, almost any smaller tier will serve you better — that's not a caveat, it's the honest positioning of this node. Fluent scales well only while each core has enough cells to stay busy relative to the data it exchanges with its neighbors, and 128 ranks pushes past that point for most CFD work. The value here is aggregate throughput.

Tell us how many cases you're running and how large they are, and we'll tell you whether SC104 or a smaller tier gets you the results faster.

Fast NVMe storage

The two 1.88 TB NVMe SSDs give substantially higher read/write throughput than SATA SSDs, plus nearly 3.76 TB of combined capacity. On a node running many jobs at once, that matters more than usual: several cases writing data files and autosaves simultaneously would saturate slower storage, and the combined capacity gives room to hold a full sweep's output without constantly clearing space.

How parallel solving works on this node

When you run Fluent in parallel, the solver partitions your mesh across the cores you assign it (using algorithms such as METIS), each core solving its share of cells and exchanging boundary data each iteration via MPI. On SC104 you'll often want to assign a subset — 16 or 32 cores per case — and run several cases side by side, rather than spreading one case across all 128. When you do use the full core count on one case, the single-socket layout is a real advantage: all MPI traffic stays on fast internal channels rather than crossing a network, which keeps overhead lower than the same rank count spread across machines.

Why rent instead of buy

A 128-core server is a substantial capital purchase that most CFD teams would leave underused. Renting it for the batch weeks and dropping to a smaller tier the rest of the time is a far better match to how this kind of work actually arrives.

How it works — you're in full control

SC104 is yours to drive directly. You connect to the node over a secure remote desktop connection and run everything yourself, exactly as you would on a local workstation:

1. Connect via remote desktop — you get full remote access to the SC104 node.

2. Set up your simulations — load your geometry and cases, configure solver settings, and run ANSYS Fluent with all 128 cores at your command, on one case or several.

3. Run and monitor in real time — start, pause, adjust, and watch your solutions as they progress, with complete control throughout.

4. Keep your results — post-process on the node or download your solution and data files whenever you're ready.

You have full authority over the node for the duration of your rental: we provide the hardware and the support, and you run the simulations your way.

Frequently asked questions

How is SC104 different from our 64- or 96-core nodes? More cores and far more cache, at the same 4.1 GHz all-core clock and the same total memory bandwidth. Since that bandwidth and the 128 GB of RAM are shared among more cores, SC104's advantage is in running more jobs at once rather than running one job faster.

Will 128 cores make my single case faster? Usually not. Most CFD cases stop scaling well long before 128 ranks — communication between partitions starts to outweigh the solving work. Send us your case and we'll check honestly; often a 32- or 64-core node is the faster answer for one case.

So what is this node actually for? Volume. A DOE sweep, a batch of design variants, a mesh-independence study, or a team sharing one machine — several cases running concurrently on separate core groups, which is where 128 cores delivers throughput nothing else here can match.

Is 128 GB enough memory for 128 cores? For running multiple moderate cases concurrently, yes. For one very large case, it's the binding limit before core count is. If your mesh needs more than 128 GB, our high-memory nodes are the right tier.

Does the clock drop when all 128 cores are working? No — AMD rates this chip at 4.1 GHz for both single-core boost and all-core boost. The clock you see on one core is the clock you get on all of them.

Is my data kept confidential? Yes.

Get started with SC104

If you have a batch of cases rather than a single one — a sweep, a study, or a team's worth of concurrent runs — SC104 gives you more total throughput than any other node here.

Contact MR CFD to run your ANSYS Fluent cases on SC104 — and we'll help you decide whether 128 cores or a smaller, faster-per-core tier gets your results sooner.