Intel Pentium 4 521 2.8GHz 800MHz OEM CPU SL8HX JM80547PG0721MM

Name: Intel Pentium 4 521 2.8GHz 800MHz OEM CPU SL8HX JM80547PG0721MM
Brand: Unbranded
SKU: B00NVN1SAY

Bottom line: The Intel Pentium 4 521 2.8GHz 800MHz OEM CPU SL8HX JM80547PG0721MM is a specs-and-price decision rather than a crowd-consensus one in the retro cpus category. Check the specification table below against one or two close alternatives — on price and spec fit, not on star ratings.

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By Mike Perry, Founder & Editor-in-Chief · Listing data updated 2026-10-05

Mike Perry — Hardware researcher since 2014. For retro PC hardware and period-correct parts, synthesises manufacturer documentation, community compatibility lists and marketplace listings rather than first-hand lab testing. Core beat: GPU performance across gaming, rendering, and local-LLM inference. About the author →

Before you buy

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Manufacturer description

Type CPU / Microprocessor Market segment Desktop Family Intel Pentium 4 Model number 521 CPU part numbers JM80547PG0721MM / HH80547PG0721MM are OEM/tray CPU BX80547PG2800EK / BX80547PGP280EK are boxed CPU Spec Codes SL8HX / SL8PP / SL9CG Frequency 2800 MHz Bus speed 800 MHz Package 775-land Flip-Chip Land Grid Array (FC-LGA4) Socket Socket 775 / LGA775 / T Microarchitecture Netburst Processor core Prescott Data width 64 bit The number of cores 1 The number of threads 2 Level 1 cache size 16 KB Level 2 cache size 1 MB

SpecPicks Verdict

SpecPicks scored Intel Pentium 4 521 2.8GHz 800MHz OEM CPU SL8HX JM80547PG0721MM using a rating × review-volume × price-fit model applied to published specs and reviews across the retro cpus category. Compare with similarly-priced alternatives in the retro cpus category before committing. Judge it on the specification table and the price rather than on sentiment: check the figures that decide your use case, then put it side-by-side with two or three close alternatives in the Compare tool before clicking through.

Common buyer scenarios for retro cpus of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the retailer's listing before purchase. Prices and stock are set by the retailer and may have moved since this page was last updated.

Full Specifications

Brand	Intel
CPU Model	Pentium
CPU Speed	2.8 GHz
CPU Socket	LGA 775
Mfr Part Number	IP4521
Processor Brand	Intel
Processor Count	1
Processor Speed	2.8 GHz
Secondary Cache	1 MB
CPU Manufacturer	Intel
Processor Series	Pentium
Processor Socket	LGA 775
Cache Memory Installed Size	1 MB

Ready to buy?

Intel Pentium 4 521 2.8GHz 800MHz OEM CPU SL8HX JM80547PG0721MM is vintage hardware; the used and vintage market on eBay carries most of the live inventory. Prices and condition vary by seller and move in real time, so we link the live listing rather than quote a cached price. It also has an Amazon listing — check it for current price and availability. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.

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