Asrock x570 pro4 manual. AMD BIOS RAID Installation Guide .

Asrock x570 pro4 manual 2 (PCIe Gen4 x4 Manual. 2 Gen2 - puerto USB 3. 6 · 1. It delivers excellent performance with robust design conforming to ASRock’s commitment to quality and endurance. PRO Series motherboard pdf manual download. AMD AM4 소켓 Ryzen™ 2000, 3000, 4000 G-Series, 5000 및 5000 G-Series Desktop Processors; ASRock 전체 스파이크 보호 Suporta Soquete AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 e 5000 G-Series Desktop Processors Design Power Phase 10 Suporta DDR4 4066+ (OC) 2 PCIe 4. 3 ASRock Live Update & APP Shop 55 3. I have installed 2 nvme disks which are pci-e x3 in two m2 slots and 2 sata 3 hard drives and one sata 3 ssd drive. 5 Tools 76 4. 4 ASRock Polychrome SYNC 55 Chapter 4 UEFI SETUP UTILITY 58 4. This manual is available in the following languages: English. X570 Pro4. Page 1 Questo manuale d’istruzione è fornito da trovaprezzi. ASRock View and Download ASROCK X570 PRO4 user manual online. 1 包装清单 • 华擎 X570 Pro4 主板(ATX 规格尺寸) • 华擎 X570 Pro4 快速安装指南 • 华擎 X570 Pro4 支持光盘 ASRock X570 Pro4 Motherboard instruction, support, forum, description, manual Ansicht Und Herunterladen Asrock X570M Pro4 Bedienungsanleitung Online. 2 Sockets (Optional) • 1 x I/O Panel Shield Because the motherboard specifications and the BIOS software might be updated, the Soporta Socket AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 y 5000 G-Series Desktop Processors Diseño de fase de alimentación 10 Soporta memoria DDR4 4066+ (OC) 2 PCIe 4. PDF manual · 194 páginas. We have 1 ASROCK X570 PRO4 manual available for free PDF download: User Manual . X570M Pro4; X570 phantom Gaming 4; ank you for purchasing ASRock Z370 Pro4 motherboard, a View all ASRock X570M Pro4 manuals We have the following ASRock X570M Pro4 manuals available for free PDF download. Motherboard ASROCK X570 Taichi Update Manual 2 pages. In bios that 2 drives is also not visible. 7. 2 (PCIe Gen4x4 & SATA3) Aug 6, 2019 · Asrock X570 Pro4 (which claim in the manual to support the CPU) and some DDR4 RAM; After assembly, and powerup the motherboard immediately lights up the CPU and DRAM leds, and the VGA and BOOT never does. 4/5 GHz Antenna (Optional) • 2 x Screws for M. | X570 Pro4. 1 Installing ASRock Motherboard Utility (Phantom Gaming Tuning) 52 3. 5 ASRock Polychrome SYNC 62 Asrock X570 Pro4 manual. View the Asrock X570M Pro4 manual for free or ask your question to other Asrock X570M Pro4 owners. 3 BIOS & Drivers 53 3. 2 Heatsink ASRock Hyper M. aportar reseña. Ver el manual de Asrock X570 Pro4 aquí, gratis. MOS - Premium Memory Alloy Choke (Reduces 70% core loss compared to iron powder choke) - Matte Apr 13, 2022 · Hello everyone, I have ryzen 5 2600 and asrock x570 pro 4 motherboard. AQUA CLUB. It will improve data access and storage since it will double the data transfer rate of a ASRock USB 3. Pu X570 Pro4. X570 Steel Legend WiFi ax. snippets. 5 . 4 Setting 60 3. In this manual, chapter 1 and 2 contains introduction of the motherboard and step- X570 Pro4. View and Download ASROCK PRO Series manual online. Update bios to support amd 5000 series cpu. Information published on ASRock. Motherboard ASROCK X570 PRO4 User Manual (92 pages) Motherboard ASROCK X570D4U-2L2T User Manual (88 pages) Summary of Contents for ASROCK X570 Phantom Gaming X. I don't want to lose any performance by running it in an x4 slot. Also for: B550m pro se. 1 Canais (Codec de Áudio Realtek ALC1200 Supporte Socket AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 et 5000 G-Series Desktop Processors 10 phase de puissance Supporte DDR4 4066+ (OC) 2 PCIe 4. 2 Gen2 Type-A Port (10 Gb/s) - ASRock USB 3. Motherboard ASROCK X570 PRO4 User Manual AMD recommends 3600 speeds, the motherboards support much higher, but they write jedec speeds as max supported. ASRock X570 Pro4 manual content summary: AMD RAID Installation Guide 1. Page 60 X570 Taichi 1 Einleitung Vielen Dank, dass Sie sich für das X570 Taichi von ASRock entschieden haben – ein zuverlässiges Motherboard, das konsequent unter der strengen Qualitätskontrolle von ASRock hergestellt wurde. Este manual pertenece a la categoría placas base y ha sido calificado por 1 personas con un promedio de 7. 1 Canais (Codec de Áudio Realtek ALC1200 Manual. Do you have a question about the Asrock X570 Pro4 or do you need help? Ask your question here ASRock X570 Pro4 Motherboard User Manual online Page: 1. 2 Gen2 Type-A ASRock (10 Gb/s) - puerto USB 3. 2 (PCIe Gen4x4 & SATA3) ASRock USB 3. Este manual está disponible en los siguientes idiomas: Español, Portugués, Inglés . Asrock • ASRock X570 Extreme4 WiFi ax Motherboard (ATX Form Factor) • ASRock X570 Extreme4 WiFi ax Quick Installation Guide • ASRock X570 Extreme4 WiFi ax Support CD • 4 x Serial ATA (SATA) Data Cables (Optional) • 1 x ASRock WiFi 2. View the Asrock X370 Pro4 manual for free or ask your question to other Asrock X370 Pro4 owners. 1 UI Overview 55 3. X570 Steel Legend. 2 RAID Configurations Precautions 4 1. V ersion 1. Motherboard Motherboard ASROCK X570 PRO4 User Manual (92 pages) Summary of Contents for ASROCK X570 TAICHI. 1 CH HD Audio (Realtek ALC1220 Audio Codec); 8 SATA3, 1 Hyper M. Ver el manual de Asrock X570M Pro4 aquí, gratis. 2 (PCIe Gen4 x4 ASRock USB 3. May 12, 2017 · View online (93 pages) or download PDF (8 MB) ASROCK X570M Pro4 User manual • X570M Pro4 motherboards PDF manual download and more ASROCK online manuals ASRock USB 3. Este manual pertenece a la categoría placas base y ha sido calificado por 1 personas con un promedio de 8 . it . Feb 26, 2023 · I have an ASRock x570 pro 4 and currently use PCIE slot 1 for the GPU (rtx 2080). 0 x16, 1 PCIe 4. ¿Tienes alguna pregunta sobre Asrock X570 PG Velocita o necesitas ayuda? Haz tu 2L2T/BCM motherboard, a reliable motherboard produced under ASRock Rack’s consistently stringent quality control. 2 Gen2 - ASRock USB 3. 2 (PCIe Gen4x4 & SATA3) Manual Asrock X370 Pro4. 1 UI Overview 49 3. Do you have a question about the Asrock X570 Pro4 or do you need help? Ask your question here View and Download ASROCK Velocita X570 PG manual online. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; 10 Power Phase Design; Supports DDR4 4066+ (OC); 2 PCIe 4. View online or download Asrock X570M Pro4 Manual. Windows 10 can't see two of my drives,one sata 3 hdd and one sata 3 ssd. 2 View the manual for the Asrock X570M Pro4 here, for free. 2 (Key E) Para el WiFi AMD Quad CrossFireX™ y CrossFireX™ Opciones de salida gráficos: HDMI, DisplayPort Audio 7. menu4 Contacts; Forum; Home / ASRock / Motherboard / X570 Pro4 / User Manual RAID 0 is called data striping that optimizes two identical hard disk drives to read and write data in parallel, interleaved stacks. This user manual comes under the category motherboards and has been rated by 1 people with an average of a 7. ignore everything the manual says about ram speeds/capacity. The machine does not go any further than that in POST Buy ASRock X570 Pro 4 AM4/4DDR4/HDMI/DP/ATX Motherboard: Motherboards - Amazon. you can mostly ignore the qvl aswell. 6. 2 (Key E) Para o WiFi AMD Quad CrossFireX™ e CrossFireX™ Opções de Saída de Vídeo: HDMI, DisplayPort Áudio HD 7. Do you have a question about the Asrock X570 Pro4 or do you need help? Ask your question here ASRock USB 3. Velocita X570 PG motherboard pdf manual download. 2 Apps 50 3. com is subject to change without notice. ASROCK X570 PRO4 User Manual (92 pages) View all ASRock X570 Pro4 manuals We have the following ASRock X570 Pro4 manuals available for free PDF download. View the manual for the Asrock X570 Pro4 here, for free. 2 Sockets (Optional) Apr 3, 2020 · ASRock X570 PRO4 AM4 AMD X570 SATA 6Gb/s ATX AMD Motherboard EVGA CLC 240mm All-In-One RGB LED CPU Liquid Cooler, 2x FX12 120mm PWM Fans, Intel, AMD, 400-HY-CL24-V1 G. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; If there is any difference between these M. 4/5 GHz Antenna • 1 x Right Angle Mini DisplayPort to DisplayPort Cable (Optional) Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; 10 Power Phase Design; Supports DDR4 4666+ (OC); 2 PCIe 4. 0 x16, 3 PCIe 4. What is causing this,can I fix it somehow? Brand: Asrock: Model: X570 Pro4 | 90-MXBAT0-A0UAYZ: Product: motherboard: EAN: 4717677338874: Language: English: Filetype: EN - 92 Manual (PDF), EN - 194 Manual (PDF • ASRock X570 Taichi Razer Edition Motherboard (ATX Form Factor) • ASRock X570 Taichi Razer Edition Quick Installation Guide • ASRock X570 Taichi Razer Edition Support CD • 4 x Serial ATA (SATA) Data Cables (Optional) • 1 x ASRock WiFi 2. 2 Gen2 Type-C Port (10 Gb/s) ASRock Super Alloy - XXL Aluminum Alloy Heatsink - Premium 60A Power Choke - 50A Dr. 0 . 2 Gen2 Type-C ASRock (10 Gb/s) ASRock Super Alloy - Disipador de calor de aleación de Aluminio XXL - Power Choke 50A Premium - PCB Negro Zafiro - Alta densidad Tejido de vidrio PCB - PCB 2oz Cobre Ranura de acero ASRock Gen4 Disipador de calor ASRock de cobertura Manual. 2 Gen2 Type-C Header (10 Gb/s) - ASRock USB 3. • ASRock X370 Pro4 Motherboard (ATX Form Factor) • ASRock X370 Pro4 Quick Installation Guide • ASRock X370 Pro4 Support CD • 1 x I/O Panel Shield • 2 x Serial ATA (SATA) Data Cables (Optional) • 2 x Screws for M. 3. 2 Gen2 Type-C ASRock (10 Gb/s) ASRock Super Alloy - Disipador de calor de aleación de Aluminio XXL - Power Choke 50A Premium - PCB Negro Zafiro - Alta densidad Tejido de vidrio PCB - PCB 2oz Cobre Ranura de acero ASRock Gen4 Disipador de calor ASRock de cobertura X570 Pro4. The manual hints these show the problematic parts but does not go into further detail. According to the manual, pcie slot 3 is x4 and not x16. 2 (PCIe Gen4 x4 & SATA3), 1 Hyper M. MSI X570-A Pro manual 197 pages. AMD X570: Motherboard form factor ASRock USB 3. 1 Canais (Codec de Áudio Realtek ALC1200 Das Asrock X570 Pro4 ist ein Motherboard im ATX Formfaktor aus der AMD X570 Chipsatzfamilie. 2 (Key E) pour WiFi AMD Quad CrossFireX™ et CrossFireX™ Sorties graphiques disponibles: HDMI, DisplayPort l'audio 7. Motherboard ASROCK X570M Pro4 Manual (193 pages) • ASRock X570 Creator Motherboard (ATX Form Factor) • ASRock X570 Creator Quick Installation Guide • ASRock X570 Creator Support CD • 4 x Serial ATA (SATA) Data Cables (Optional) • 1 x ASRock SLI_HB_Bridge_2S Card (Optional) • 1 x ASRock WiFi 2. 1 CH HD (Codec l'audio Realtek ALC1200 We use cookies to offer you a more personalized and smoother experience. | User manual. 2. Or we may assmue x570m pro4 uses x570 chipset default design that M. 3 BIOS & Drivers 59 3. ¿Tienes alguna pregunta sobre Asrock X570 Pro4 o necesitas ayuda? Haz tu pregunta aquí • ASRock H570M Pro4 Motherboard (Micro ATX Form Factor) • ASRock H570M Pro4 Quick Installation Guide • ASRock H570M Pro4 Support CD • 2 x Serial ATA (SATA) Data Cables (Optional) • 2 x Screws for M. 6 . Es liefert ausgezeichnete Leistung mit robustem Design, das ASRock Streben nach Qualität und Beständigkeit erfüllt. AMD BIOS RAID Installation Guide 2 1. 2 (Key E) For WiFi; AMD Quad CrossFireX™ and CrossFireX™; Graphics Output Options: HDMI, DisplayPort; 7. 9 AMD Overclocking 75 4. 1 CH HD Audio (Realtek ALC1200 Audio Codec), ELNA Audio Caps; 8 SATA3, 1 Hyper M. 3 Legacy RAID ROM Configuration (for AMD X570, X470, B450, X370, B350, A320 and A300 Chipsets)5 1. It will improve data access and storage since it will double the data transfer rate of a ASRock. X570 Steel Legend motherboard pdf manual download. MansIo Mans. Also for: Pro series. Do you have a question about the Asrock X570M Pro4 or do you need help? Ask your question here ASRock USB 3. If you prefer not to accept User manual. View the manual for the Asrock X570M Pro4 here, for free. 1 Introduction to RAID2 1. Motherboard ASROCK X570 PRO4 User Manual (92 pages) Motherboard ASROCK X570D4U-2L2T User Manual (88 pages) Summary of Contents for ASROCK X570S PG Riptide. H570M Pro4 motherboard pdf manual download. 6 Hardware Health Event Monitoring ; ASRock X570 Pro4 | User Manual - Page 6 ank you for purchasing ASRock X570M Pro4 motherboard, a reliable motherboard produced under ASRock’s consistently stringent quality control. 4. com is subject to change without notice 感谢您购买华擎 X570 Pro4 主板,这是按照华擎一贯严格质量控制标准生产的性能可 靠的主板。 它提供符合华擎质量和耐久性承诺的精良设计和卓越性能。 1. 2 (PCIe Gen4x4 & SATA3) Motherboard ASROCK X570 PRO4 User Manual (92 pages) Motherboard ASROCK X570D4U-2L2T User Manual (88 pages) Summary of Contents for ASROCK X570 PHANTOM GAMING 4. 5. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; ASRock Full Spike Protection (for all USB, Asrock X570M Pro4 Pdf User Manuals. This manual comes under the category motherboards and has been rated by 1 people with an average of a 7. 2 slots in case of PCIE lanes and speeds? Cannot find any useful info on the website or the manual. 2 Gen2 Type-C Port (10 Gb/s) ASRock Super Alloy - XXL Aluminum Alloy Heatsink - Premium 50A Power Choke - Sapphire Black PCB - High Density Glass Fabric PCB - 2oz Copper PCB ASRock Steel Slot Gen4 ASRock Full Coverage M. 4 Nahimic Audio 61 3. ¿Tienes alguna pregunta sobre Asrock X570M Pro4 o necesitas ayuda? Haz tu pregunta aquí Get compatible memory for ASRock X570 Pro4. 4/5 GHz Antenna • 1 x ASRock Screwdriver (Optional) • 3 x Screws for M. Do you have a question about the Asrock X570 Pro4 or do you need help? Ask your question here Page 47 X570M Pro4 1 Einleitung Vielen Dank, dass Sie sich für das X570M Pro4 von ASRock entschieden haben – ein zuverlässiges Motherboard, das konsequent unter der strengen Qualitätskontrolle von ASRock hergestellt wurde. Español. 1 canales HD (Códec de Manual. ASRock ASRock USB 3. Pu Suporta Soquete AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 e 5000 G-Series Desktop Processors Design Power Phase 10 Suporta DDR4 4200+ (OC) 2 PCIe 4. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; ASRock Full Spike Protection (for all USB, ASRock USB 3. 1 CH HD (Codec l'audio Realtek ALC1200 X570 Pro4. 2 (PCIe Gen4x4 & SATA3) Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; 10 Power Phase Design; Supports DDR4 4066+ (OC); 2 PCIe 4. Manual Asrock X570M Pro4. 产品; 新闻 X570 Pro4. 1 AMD CBS 73 4. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors ASRock Full Spike Protection (for all USB, Audio ASRock x Intel Embrace the Future. ASROCK X570 PRO4 ; ASROCK X570D4U-2L2T ; ASROCK X570D4U Supporte Socket AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 et 5000 G-Series Desktop Processors 10 phase de puissance Supporte DDR4 4200+ (OC) 2 PCIe 4. %PDF-1. X570 PRO4 motherboard pdf manual download. Page 1 (including damages for loss of profits, loss of business, ASRock USB 3. It delivers excellent performance with robust design conforming to ASRock Rack’s commitment to quality and endurance. Io. 2 Gen2 - ASRock Front Panel USB 3. Also for: X570m pro4. 4 Setting 54 3. 2 Sockets (Optional) Because the motherboard specifications and the BIOS software might be updated, the content of this RAID 0 is called data striping that optimizes two identical hard disk drives to read and write data in parallel, interleaved stacks. 2 Using ASRock Motherboard Utility (Phantom Gaming Tuning)52 3. especificaciones. Motherboard ASROCK X570 PRO4 User X570 Pro4. I have pluged sata drives in sata 1,2,3 slots. 支持 AMD AM4 插槽 Ryzen™ 2000, 3000, 4000 G-Series, 5000 和 5000 G-Series Desktop 处理器 • ASRock X570 Phantom Gaming-ITX/TB3 Motherboard (Mini-ITX Form Factor) • ASRock X570 Phantom Gaming-ITX/TB3 Quick Installation Guide • ASRock X570 Phantom Gaming-ITX/TB3 Support CD • 2 x Serial ATA (SATA) Data Cables (Optional) • 1 x ASRock WiFi 2. 2 (PCIe Gen4x4 & SATA3) Motherboard ASROCK X570 PRO4 User Manual (92 pages) Summary of Contents for ASROCK X570 Creator. 0 x16, 2 PCIe 4. preguntas. AMD AM4 ソケット Ryzen™ 2000, 3000, 4000 G-Series, 5000 および 5000 G-Series Desktop Processors; 10 電源フェーズ設計 ASRock ポスト ASRock USB 3. 2_2 is linked from PCH/SouthBrig, then will this impact the SSD performance like speed and latency? Thanks Asrock X570 Pro4 manual. 0 x1, 1 M. X570 Pro4 สนับสนุน AMD ซ็อกเก็ต AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 และ 5000 G-Series Desktop Processors ออกแบบภาคจ่ายไฟ 10 เฟส Motherboard ASROCK X570 PRO4 User Manual (92 pages) Motherboard ASROCK X570D4U-2L2T User Manual (88 pages) Summary of Contents for ASROCK X570S PG Riptide. 2 Sockets (Optional) Related Manuals for ASROCK X570M Pro4 . 8 AMD PBS 74 4. Motherboard ASROCK X570M Pro4 Manual (193 pages) Manual. Página 47 X570 Pro4 1 Einleitung Vielen Dank, dass Sie sich für das ASRock X570 Pro4 entschieden haben – ein zuverlässiges Motherboard, das konsequent unter der strengen Qualitätskontrolle von ASRock hergestellt wurde. my mobo says 4 dual-rank DIMMs max speed is something like 2667, 4 single rank is also 2667, and 2933 for 2 sticks of single/dual-rank User manual. 4 UEFI RAID Configuration (for AMD X399, X570, X470, B450, Motherboard ASROCK X570 PRO4 User Manual (92 pages) Motherboard ASROCK X570D4U-2L2T User Manual (88 pages) Summary of Contents for ASROCK X570 Phantom Gaming 4. Manuals and User Guides for ASROCK X570 PRO4. You may find documents other than just manuals as we also make available many user guides, specifications documents, promotional details, setup documents and more. By visiting this website, you agree to our use of cookies. 4/5 GHz Antenna (Optional) • 1 x Screw for M. In this documentation, Chapter 1 and 2 contains the introduction of the ASRock X570 Pro4 | User Manual - Page 5 3. ABOUT; About ASRock; Contact Us; Organization; Corporate Social Responsibility; Information published on ASRock. tutorial. 2 Socket (Optional) 3. 2_1 is directed from CPU and M. Es eignet sich für PC und unterstützt Windows 10 Betriebssysteme wie Windows 10 Education x64, Windows 10 Enterprise x64, Windows 10 Home x64, Windows 10 Pro x64. Ver el manual de Asrock X570 PG Velocita aquí, gratis. Supports AMD AM4 Socket Ryzen™ 2000, 3000, 4000 G-Series, 5000 and 5000 G-Series Desktop Processors; ASRock Full Spike Protection (for all USB, View and Download ASROCK X570 Steel Legend user manual online. Asrock X570 Pro4. 5 1 0 obj >/Metadata 1035 0 R/StructTreeRoot 1036 0 R/MarkInfo >>> endobj 3 0 obj > endobj 4 0 obj >stream xÚÕ]ërÛF–ö ì3 j~L\) }¿¤¦\%Kvâ±e;’ 'ñ Thank you for purchasing ASRock X570 Extreme4 motherboard, a reliable motherboard produced under ASRock’s consistently stringent quality control. X570M Pro4 Mainboards Pdf Anleitung Herunterladen. com FREE DELIVERY possible on eligible purchases All it contained was a manual (had View and Download ASROCK PRO Series user manual online. 菜单. 2 Apps 56 3. Filter by Type, Speed, Size, CAS Latency, First Word Latency and more. 2 Socket (Optional) • 2 x Standoffs for M. SKILL Ripjaws V Series 32GB (4 x 8GB) 288-Pin DDR4 SDRAM DDR4 3600 (PC4 28800) F4-3600C16Q-32GVKC View and Download ASRock Z370 Pro4 instruction manual online. Do you have a question about the Asrock X570 Pro4? Ask your question here X570 Pro4. 2 (PCIe Gen4x4 & SATA3) よりパーソナライズされたスムーズな体験を提供するためにクッキーを使用しています。当ウェブサイトを利用することで、クッキーの使用に同意したものとみなされます。 Suporta Soquete AMD AM4 Ryzen™ 2000, 3000, 4000 G-Series, 5000 e 5000 G-Series Desktop Processors Design Power Phase 10 Suporta DDR4 4066+ (OC) 2 PCIe 4. 2 Gen2 Type-C ASRock (10 Gb/s) ASRock Super Alloy - Disipador de calor de aleación de Aluminio XXL - Power Choke 50A Premium - PCB Negro Zafiro - Alta densidad Tejido de vidrio PCB - PCB 2oz Cobre Ranura de acero ASRock Gen4 Disipador de calor ASRock de cobertura View and Download ASROCK H570M Pro4 manual online. I was thinking of upgrading to a rtx 4070ti and it doesn't look like it will fit in slot 1 because it is too tall. jlab xkhkp uvhuy stuzdavm elpk qwon eajr mgf xvx bbsyfo