Understanding the Dell E93839 Go to product viewer dialog for this item. Motherboard: Specs, Identification, and Schematics Dell E93839
" is a widely searched part number, though it can be a bit confusing for those trying to track down technical documentation. This identifier is actually a UL (Underwriters Laboratories) certification number rather than a specific motherboard model. It appears on several different boards produced by manufacturers like Foxconn or BQTEC for various Dell OptiPlex systems.
If you are looking for high-quality schematics for repair or tinkering, here is what you need to know to find the right files. 1. Identifying Your Specific Board
Because "E93839" covers multiple generations of hardware, you must first find the true Part Number (P/N) to locate a matching schematic. E93839 - Dell - Tech Atlantix
The model number (often with the suffix ) is actually an identifying mark from Foxconn, the manufacturer that produced motherboards for brands like
For Dell systems, this specific board is most commonly found in the Dell OptiPlex 390
. Full "schematics"—technical circuit diagrams used for component-level repair—are proprietary and rarely released by Dell. However, you can find complete documentation for the motherboard's layout, pinouts, and hardware specifications by using the official Dell Support Manuals page for the OptiPlex 390 Motherboard Specifications (OptiPlex 390)
LGA 1155, supporting 2nd Generation Intel Core i3/i5 "Sandy Bridge" processors. 2 slots supporting DDR3 SDRAM, with a maximum capacity of Typically Intel H61. Expansion:
PCIe x16 slot for graphics cards and PCIe x1 slots for other peripherals. MemoryStock How to Find Your Specific Documentation
Since "E93839" is a manufacturer part number used across multiple models, the best way to get a high-quality layout and wiring guide is to identify your unique Dell Service Tag Locate the Service Tag: Dell E93839 Motherboard Schematic High Quality
Look for a 7-character alphanumeric code on a sticker on the back or side of your PC. Search Dell Support: Enter this tag on the Dell Drivers & Downloads Download Manuals: Look for the "Owner’s Manual" "Service Manual."
These high-quality PDFs contain the motherboard component map and front-panel connector diagrams you are likely looking for. Common Diagnostic Codes
If you are looking for a schematic to troubleshoot a failure, check the front power LED for blink codes first: Run a Motherboard Built-in Test (M-BIST) | Dell US 25 Mar 2025 —
The Dell E93839 is not a specific motherboard model but a regulatory mark (UL certification number) found on several boards, most commonly those used in the Dell OptiPlex 780 series. Schematic and Manual Resources
For full circuit diagrams and component-level repair, you can access these high-quality resources:
Circuit Schematic (PDF): Detailed schematics for the OptiPlex 780 (often associated with motherboard part 0T656F) are available for download on ChinaFix.
Official Service Manual: Dell provides layout diagrams and connector descriptions in the OptiPlex 780 Service Manual.
Component-Level Guide: Technical boardviews and PDFs can sometimes be found in archives like DeviceDB. Hardware Specifications Based on the OptiPlex 780 implementation: Socket: LGA 775 (Supports Intel Core 2 Duo, Pentium). Chipset: Intel Q45 / ICH10. Memory: 4x DDR3 DIMM slots (up to 16GB, 1066/1333 MHz). Expansion: 1x PCIe x16, 2x PCI.
I/O Ports: 6x USB 2.0 (rear), VGA, DisplayPort, eSATA, Serial, Parallel. Front Panel Pinout (Standard Case Swap) Understanding the Dell E93839 Go to product viewer
If you are performing a "case swap" to a standard ATX case, the proprietary 34-pin front panel header typically follows this common Dell pattern:
Power Switch: Pins 20 and 9 (or shorting specific pins based on the sub-model). HDD LED: Pins 22 and 4. Power LED: Pin 23 (+) and Pin 4 (-). E93839 - Dell - Tech Atlantix
The Dell E93839 designation refers to a UL certification number found on various Foxconn-manufactured boards rather than a specific model number, requiring the identification of a Dell Part Number (DP/N) or PCB marking for accurate schematics. The board is frequently associated with the Dell OptiPlex 780, which typically features an LGA 775 socket and DDR3 RAM. Resources for schematics include enthusiast repair forums such as BadCaps.net, VinaFix, and Lab One Care. You can find technical discussions and potential schematics at the BadCaps.net forum.
To find the correct technical documentation, locate the white rectangular or square barcode sticker on your board. How to identify Dell motherboard part number
The Dell E93839 is not a specific motherboard model name, but rather a UL identification number (E93839) often found on boards manufactured by Foxconn for Dell and HP systems. Detailed schematics are rarely released publicly by manufacturers, but technical specifications and system board layouts for the specific models associated with this number are available in official service manuals. Associated Dell Models
This identification number is most commonly linked to the motherboards of the following Dell OptiPlex series: REFURB Dell OptiPlex 780 SFF PC Rp 2.362.757(US$136,95) eBay - buy-best Go to product viewer dialog for this item.
Utilizes the Intel Q45 Express chipset and supports LGA1155 socket processors.
Dell Optiplex 790 Sff Intel I5-2400 3.1ghz 8gb Ram Amd Radeon 6450 1gb Rp 862.635(US$50,00) Go to product viewer dialog for this item.
Features LGA 1155 socket support for 2nd Gen Intel Core processors and DDR3 memory. System Chipset: Intel Sunrise Point-LP (100/140 series) PCH:
Dell Optiplex 390 Mt Computer Fisso Desktop Vga Hdmi Dvd-Rw Pc - Windows Xp - Celeron Rp 1.618.027(€80,00) Go to product viewer dialog for this item.
Often found in Mini-Tower (MT) and Small Form Factor (SFF) configurations. Technical Specifications (Common for E93839 marked boards) DELL OPTIPLEX 390
Sometimes, technicians sell physical repair binders containing high-quality prints of Dell schematics. Alternatively, buying a non-working E93839 board for $20 to visually trace circuits is a low-tech but effective backup plan.
A genuine high-resolution schematic (usually in .pdf format) for board number LA-B753P (the reference designator for E93839) includes:
🔍 High quality means: Component values, test point voltages, signal names (SUSCLK, SLP_S5#), and resistor network details are legible even at 200% zoom.
If you’re reading this, you likely have a Dell OptiPlex (7040, 5040, or 3040) or a Precision Tower (3420) on your bench with the infamous E93839 motherboard. You’ve searched for hours, found blurry, watermarked, or incomplete diagrams, and you need a high-quality schematic to troubleshoot.
This post will not send you on a wild goose chase. Instead, I’ll explain exactly what the E93839 board is, where to find a legitimate, readable schematic, and how to use it to fix common failures.
Corrupt BIOS is a nightmare on the E93839. Look for the SPI flash ROM (usually Winbond 25Q64). A high-quality schematic will clearly label pin 1 (CS), pin 6 (CLK), and pin 2 (DO). It will also show the exact voltage (3.3V standby) required for programming.
Because Dell keeps these documents under strict Non-Disclosure Agreements (NDAs), you cannot simply Google the file and click the first link. Most free sites are filled with malware or garbage scans. Here are the professional methods:
F2 or F7 on the E93839). High-quality scan shows it as "Polyfuse 1.1A." Test continuity; it's open. Replace it for $0.50.