With the capabilities of your M/B it seems a waste to be running 266 RAM, even though the Motherboard can run it, that would be like crimping a waterhose, but you could do it and if you're having problems you may need to adjust your RAM timings, you didn't mention the other RAM modules you're running but if they're not the same speed as the 266 but faster then you would be at a serious disadvantage to run the 266 because the other RAM modules would clock down to 266, and you would seriously crimp your performance.
MSI 865PE NEO2-PLATINUM
CPU
• Supports Intel® Pentium 4 Northwood/Prescott (Socket 478) processors.
• FSB 400 (for Northwood only), 533, 800MHz
• Supports up to 3.6GHz or higher speed.
Chipset
• Intel® 865PE Chipset
- Supports FSB 800/533/400MHz
- Supports AGP 8X interface
- Supports DDR 400/333/266 memory interface
• Intel® ICH5 Chipset
- Hi-Speed USB (USB2.0) controller, 480Mb/sec, 8 ports
- 2 Serial ATA/ 150 ports
- 2 channel Ultra ATA 100 bus Master IDE controller
- PCI Master v2.3, I/O APIC
- Supports both ACPI and legacy APM power management
Main Memory
• Supports four unbuffered DIMM of 2.5 Volt DDR SDRAM
• Supports up to 4GB memory size without ECC
• Supports Dual channel DDR266/333/400/433/466/500/533 MHz and up. (DDR433/466/500/533 are overclocking spec, also refer to User's Manual)
DDR433/450/466/500/533 Memory Modules Qualified Vender List
DDR400 Memory Modules Qualified Vender List
Slots
• One AGP slot supports 8X/4X at 0.8V (AGP 3.0) or 4X at 1.5V (3.3V is not supported)
• Five 32-bit v2.3 Master PCI bus slots (support 3.3V/5V PCI bus interface)
BIOS
• The mainboard BIOS provides "Plug & Play" BIOS which detects the peripheral devices and expansion cards of the board automatically.
• The mainboard provides a Desktop Management Interface (DMI) function which records your mainboard specifications.
On-Board IDE
Dual Ultra DMA 66/ 100 IDE controllers integrated in ICH5
- Supports PIO, Bus Master operation modes
- Can connect up to four Ultra ATA drives
Serial ATA/ 150 controller integrated in ICH5
- Up to 150MB/s transfer speed
- Can connect up to 2 Serial ATA drives
Audio
AC97 link controller integrated in Intel® 865PE Chipset
6-channel audio codec Realtek ALC655
- Compliance with AC97 v2.3 Spec.
- Meet PC2001 audio performance requirement
LAN
Realtek® 8110S
- Integrated Fast Ethernet MAC and PHY in one chip
- Supports 10Mb/s, 100Mb/s, 1000Mb/s
- Compliance with PCI 2.2
- Supports ACPI Power Management
On-Board Peripherals
- 1 floppy port supports 1 FDDs with 360K, 720K, 1.2M, 1.44M and 2.88Mbytes
- 1 serial port COM1
- 1 parallel port supports SPP/EPP/ECP mode
- 8 USB 2.0 ports (Rear x 4 / Front x 4)
- 1 Line-In / Line-Out / Mic-In audio port
- SPDIF Out-Optical audio port
- 1 RJ45 LAN jack
Dimension
ATX Form Factor: 30.5 cm (L) x 24.5 cm (W)
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