Yes, thanks @petewarden the basic SDRAM concept is solved, but when I try to use it with the arduino TensorflowLite HelloWorld (sine wave) it compiles on the arduino  Portenta but then gives me the red LED flash of death.
A starting point, I did get the Portenta working using regular TensorflowLite HelloWorld without and SDRAM saving of the Model. Just the arduino_output_handler.cpp file has analogWrite() to the builtin LED which kills the program, since the Portenta Analog pins strangely can’t do PWM.
Changing
analogWrite(led, brightness);

to
digitalWrite(led, brightness);
delay(3);

then works fine (note: it is really fast so the delay helps see the sine wave better).
Then:
The code I was running to test SDRAM is here in the main “hello_world.ino” file
/* Copyright 2020 The TensorFlow Authors. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==============================================================================*/

#include <TensorFlowLite.h>

#include "main_functions.h"

#include "tensorflow/lite/micro/all_ops_resolver.h"
#include "constants.h"
#include "model.h"
#include "output_handler.h"
#include "tensorflow/lite/micro/micro_error_reporter.h"
#include "tensorflow/lite/micro/micro_interpreter.h"
#include "tensorflow/lite/schema/schema_generated.h"
#include "tensorflow/lite/version.h"


#include <SDRAM.h>
#define ALIGN_PTR(p,a)   ((p & (a-1)) ?(((uintptr_t)p + a) & ~(uintptr_t)(a-1)) : p)
SDRAMClass mySDRAM;




// define SDRAM pointer
alignas(8) unsigned char *sdram_mem;
alignas(8) unsigned char *sdram_tflite; // 32-byte aligned



// Globals, used for compatibility with Arduino-style sketches.
namespace {
tflite::ErrorReporter* error_reporter = nullptr;
const tflite::Model* model = nullptr;
tflite::MicroInterpreter* interpreter = nullptr;
TfLiteTensor* input = nullptr;
TfLiteTensor* output = nullptr;
int inference_count = 0;

constexpr int kTensorArenaSize = 2000;
uint8_t tensor_arena[kTensorArenaSize];
}  // namespace

// The name of this function is important for Arduino compatibility.
void setup() {


   mySDRAM.begin(SDRAM_START_ADDRESS);   

   // setup SDRAM memory block
   sdram_mem = (alignas(8)  unsigned char *) SDRAM.malloc(4 + 32 /*alignment*/);
   sdram_tflite = (alignas(8)  unsigned char *)ALIGN_PTR((uintptr_t)sdram_mem, 32);
const int model_tflite_len = 2640;
const int g_model_len = 2640;
//const int g_model_len = 2488;

   memcpy(sdram_tflite, "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", model_tflite_len);


  
  // Set up logging. Google style is to avoid globals or statics because of
  // lifetime uncertainty, but since this has a trivial destructor it's okay.
  // NOLINTNEXTLINE(runtime-global-variables)
  static tflite::MicroErrorReporter micro_error_reporter;
  error_reporter = &micro_error_reporter;

  // Map the model into a usable data structure. This doesn't involve any
  // copying or parsing, it's a very lightweight operation.





  
 // model = tflite::GetModel(g_model);
  model = tflite::GetModel(sdram_tflite);
  if (model->version() != TFLITE_SCHEMA_VERSION) {
    TF_LITE_REPORT_ERROR(error_reporter,
                         "Model provided is schema version %d not equal "
                         "to supported version %d.",
                         model->version(), TFLITE_SCHEMA_VERSION);
    return;
  }

  // This pulls in all the operation implementations we need.
  // NOLINTNEXTLINE(runtime-global-variables)
  static tflite::AllOpsResolver resolver;

  // Build an interpreter to run the model with.
  static tflite::MicroInterpreter static_interpreter(
      model, resolver, tensor_arena, kTensorArenaSize, error_reporter);
  interpreter = &static_interpreter;

  // Allocate memory from the tensor_arena for the model's tensors.
  TfLiteStatus allocate_status = interpreter->AllocateTensors();
  if (allocate_status != kTfLiteOk) {
    TF_LITE_REPORT_ERROR(error_reporter, "AllocateTensors() failed");
    return;
  }

  // Obtain pointers to the model's input and output tensors.
  input = interpreter->input(0);
  output = interpreter->output(0);

  // Keep track of how many inferences we have performed.
  inference_count = 0;
}

// The name of this function is important for Arduino compatibility.
void loop() {
  // Calculate an x value to feed into the model. We compare the current
  // inference_count to the number of inferences per cycle to determine
  // our position within the range of possible x values the model was
  // trained on, and use this to calculate a value.
  float position = static_cast<float>(inference_count) /
                   static_cast<float>(kInferencesPerCycle);
  float x = position * kXrange;

  // Quantize the input from floating-point to integer
  int8_t x_quantized = x / input->params.scale + input->params.zero_point;
  // Place the quantized input in the model's input tensor
  input->data.int8[0] = x_quantized;

  // Run inference, and report any error
  TfLiteStatus invoke_status = interpreter->Invoke();
  if (invoke_status != kTfLiteOk) {
    TF_LITE_REPORT_ERROR(error_reporter, "Invoke failed on x: %f\n",
                         static_cast<double>(x));
    return;
  }

  // Obtain the quantized output from model's output tensor
  int8_t y_quantized = output->data.int8[0];
  // Dequantize the output from integer to floating-point
  float y = (y_quantized - output->params.zero_point) * output->params.scale;

  // Output the results. A custom HandleOutput function can be implemented
  // for each supported hardware target.
  HandleOutput(error_reporter, x, y);

  // Increment the inference_counter, and reset it if we have reached
  // the total number per cycle
  inference_count += 1;
  if (inference_count >= kInferencesPerCycle) inference_count = 0;
}



This code compiles, but crashes on startup. Any suggestion to try would be appreciated, but not a huge deal as I have lots of other ML projects on the go.