Here are some speed results for RAM according to Memtest86+ on some machines that I have run. Note that the reported speed varies between runs by a few percent.

Thinkpad 600e PentiumII 400Mhz PC-66 RAM (2 DIMMs) | 174MB/s |

Compaq P3-866MHz PC133 RAM (3 DIMMs, 2*128 + 256) | 190MB/s |

Compaq Athlon 1GHz PC133 RAM (3 DIMMs) | 219MB/s |

Compaq P3-800MHz PC133 RAM (1 DIMM) | 270MB/s |

Compaq P3-800MHz PC133 RAM (3 DIMMs, 2*128 + 256) | 240MB/s |

Compaq P4 1.5GHz PC133 RAM (3 DIMMs) | 486MB/s |

Compaq P4 1.5GHz PC133 RAM (1 or 2 DIMMs) | 490MB/s |

EeePC 701, DDR2-665 PC2-5300 running at DDR2-333 speed | 798MB/s |

HP Celeron 1.8GHz PC2100/DDR266 (1 DIMM) | 824MB/s |

HP Celeron 2.4GHz PC2100/DDR266 RAM (2 DIMMs) | 984MB/s |

Celeron D (32bit) 2.93GHz PC2400/DDR300 PC3200 RAM | 1,140MB/s |

HP Celeron 2.4GHz PC2700/DDR333 RAM (2 DIMMs) | 1,027MB/s |

HP Celeron 2.4GHz PC2700/DDR333 RAM (2 DIMMs) | 1,375MB/s |

Dell PowerEdge T105 Dual-core Opteron 1212 (2GHz) single DDR2-667 ECC RAM | 1,670MB/s |

Dell PowerEdge T105 Dual-core Opteron 1212 (2GHz) pair of DDR2-667 ECC RAM | 1,826MB/s |

NEC Pentium E2160 1.8GHz DDR663 (two mismatched DIMMs) | 2,307MB/s |

IBM Pentium E2160 1.8GHz DDR2-667 PC2-5300 (single DIMM) | 2,371MB/s |

IBM Pentium E2160 1.8GHz PC2-4200 (paired DIMMs) | 2,436MB/s |

NEC Pentium E4600 2.4GHz DDR2-667 PC2-5300 (single DIMM) | 2,528MB/s |

NEC Pentium D 2.8GHz DDR 533 (unpaired DIMMS) | 1,600MB/s |

NEC Pentium D 2.8GHz DDR 533 (paired DIMMS) | 2,600MB/s |

Thinkpad T61 DDR2-665 PC2-5300 (single DIMM) | 2,023MB/s |

Thinkpad T61 DDR2-665 PC2-5300 (paired or mismatched DIMMs) | 2,823MB/s |

Core Gen2 2492MHz | 3,804MB/s |

Core Gen2 2492MHz 2 DIMMs | 3,930MB/s |

Q8400 2*PC6400 | 4,830MB/s |

Dell PowerEdge T320 E5-2430 2.2GHz, DDR3-1600 PC3-12800 (single DIMM) | 7,692MB/s |

Intel X3450 2.67GHz, DDR3-1066 (4 DIMMs) | 10.0GB/s |

Thinkpad X1 Yoga Gen3 i5-8350U 1.7GHz, LPDDR3-2133 (paired DIMMs) Battery/AC | 7,140MB/s 10.3GB/s |

Dell PowerEdge T320 E5-2430 2.2GHz, DDR3-1600 PC3-12800 (pair DIMMs) | 11.3GB/s |

Dell Lattitude 5590 laptop I5-8350U 1.7GHz, DDR4-2400 PC4-19200 (paired DIMMs) | 12.2GB/s |

Dell PowerEdge T30 Core E3-1225 3.3GHz, DDR4-2133 PC4-17000 (single DIMM) | 12.5GB/s |

Dell PowerEdge T320 E5-2430 2.2GHz, DDR3-1600 PC3-12800 (3 DIMMs) | 13.5GB/s |

Dell Latitude 7480 i7-7660U, DDR4-2400 (paired DIMMs) | 13.7GB/s |

Dell Lattitude 7410 Laptop i7-10610U DDR4 | 14.6GB/s |

Dell Lattitude 7400 2in1 Laptop i7-8665U DDR3 | 14.8GB/s |

HP Z640 E5-1650v3, DDR4 (paired DIMMs) | 15.5GB/s |

Thinkpad X1 Carbon Gen5 i5-6300U 2.40GHz, DDR3-1867 (paired DIMMs) Battery/AC | 7,640MB/s 16.2GB/s |

i7-2600 3.4GHz, DDR3-1333 PC3-10600 (paired DIMMs) | 16.6GB/s |

AMD Ryzen 5 3600 DDR4-3200 (4*8G DIMMs) | 17.3GB/s |

Dell PowerEdge T110-II Core i3-3220 3.3GHz, DDR3-1600 PC3-12800 (paired DIMMs) | 17.9GB/s |

DDR266 theoretically can do 2100MB/s, but I’ve only seen it do 984MB/s (with two DIMMs).