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Synology 16 GB DDR4 ECC SO-DIMM Memory Module for NAS (D4ES03-16G)

Genuine Synology 16 GB unbuffered DDR4 ECC SO-DIMM memory module, to add RAM to DiskStation and RackStation NAS from series 21 to 26, including the DS925+, DS1825+, DS923+ and RS1226+.

  • 16 GB of DDR4 in a single module
  • ECC error correction
  • 260-pin SO-DIMM, unbuffered
  • Genuine module validated by Synology
  • Compatible with Synology NAS series 21 to 26
  • Up to 32 GB on a DS925+ with two modules
Ref.: D4ES03-16G
New
Synology 16 GB DDR4 ECC SO-DIMM Memory Module for NAS (D4ES03-16G)

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What the image does not guarantee:

  • Design and revisions : one component is produced by several partner manufacturers: cooler, backplate, RGB lighting and printing change with the version delivered.
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What is binding: the product title, this page's technical specifications, the description and, when provided, the manufacturer's PDF datasheet available in the downloads.

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21 456,00 DHincl. VAT

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3 ways to get it

In-store collection — free

Casablanca store
Available within 24 h
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Manoir des Roses Residence, Lot 18, El Hachmi El Filali Boulevard, Bachkou Roundabout, Casablanca

Opening hours

  • Mon–Fri: 10am – 7pm
  • Sat: 10am – 2pm
  • Closed on Sundays and public holidays

Payment on site: cash, bank card via terminal, certified cheque.

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Témara pickup point
Available within 48 h
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Hassan II Boulevard, Les Perles de Témara Residence, Building 5, Apartment 2, Témara

Opening hours

  • Mon–Thu: 8.30am – 6pm
  • Fri: 8.30am – 1.30pm / 2.30pm – 6pm
  • Sat: 8.30am – 12.30pm
  • Closed on Sundays and public holidays

Payment on site: cash, bank card via terminal, certified cheque.

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Delivery anywhere in Morocco

free

In stockReceive it between Mon 9 Nov and Wed 11 Nov ·

Delivery to your address

Receive it between Mon 9 Nov and Wed 11 Nov — free delivery all over Morocco

The estimate is refined using actual delivery rounds to your city.

  • Free delivery from 3 000 DH of purchases, all over Morocco.
  • Below that, the same rate in every city for parcels up to 30 kg (delivery to your home or workplace) — the exact amount is shown above, then in the basket.
  • Above 30 kg, the rate follows the parcel's weight. In Casablanca, the flat rate holds up to 120 kg.
  • You are notified by SMS, then called by the courier before your parcel is handed over (delivered by Sapress).
  • Observed delivery time: 1 to 5 working days depending on the city.

Casablanca store

Free pickup

Available within 24 hWe bring it there and call you when it arrives

Témara pickup point

Free pickup

Available within 48 hWe bring it there and call you when it arrives

5 years warranty — free repair in Morocco if it breaks down during the warranty period

5 years manufacturer's warranty

This product is covered for 5 years by a manufacturer's warranty (the brand's official warranty). Your iris.ma invoice serves as the warranty document: keep it safe.

A problem with your product? Don't worry: contact us by phone, WhatsApp or e-mail. Depending on the brand, we direct you either straight to the repairer appointed by the brand to fix your product, or to us — and we take care of the rest.

  • If a repair is possible, it is carried out free of charge.
  • If the product cannot be repaired, the brand offers an exchange for another product.
  • If no product is available, a refund is issued as soon as the brand confirms it.

Faulty straight out of the box? Some brands offer an immediate exchange, others a repair. Contact us to find out what applies to your product.

The warranty covers breakdowns occurring under normal use, as defined by the brand's terms. Product breakage (drop, impact, liquid…) is not covered, nor are certain consumable parts.

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New, never opened — our commitment

All our products are new, delivered in their sealed original packaging.

We commit to never sending you a product that has been opened, unboxed or returned by another customer — even one “just opened for checking”.

Any doubt on delivery (damaged box, seal already opened)? Point it out to the courier or contact us immediately: we take the product back and send you another one.

Sales invoice

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Ordering for a company? Using the details you give at checkout (company name and ICE), the invoice is issued in your company's name, with its ICE.

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100% secure payment: Bank transfer · Bank card · Certified cheque

Accepted payment methods

Bank transfer

Simply transfer the amount shown to account 007 826 0002684000000426 89 — SGM2I, Attijariwafa bank. The rest (the reference to quote, sending us the proof, tracking) is explained right after confirmation and by email. An instant transfer is recommended: it saves you 24 hours on the delivery time.

Bank card

Your everyday Moroccan bank card is enough — Visa, Mastercard or CMI, no special card required. Foreign cards are accepted too. Secure payment by Attijari Payment.

Certified cheque

Certified cheque payable to “sgm2i”. Have your bank certify the cheque, then send us a copy on WhatsApp (+212 6 64 10 46 24) or to service.client@iris.ma — we dispatch as soon as we receive it.

The methods offered depend on the order total and the carrier — checkout shows the final list.

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Product overview

Genuine Synology memory module to add RAM to a compatible DiskStation or RackStation NAS and run more applications at the same time.
Memory: 16 GB of unbuffered DDR4 ECC
Form factor: 260-pin SO-DIMM · one module
Reliability: ECC error correction detects and corrects memory errors on a server that runs day and night
Compatibility: Synology NAS from series 21 to 26, including the DS925+, DS1825+, DS923+ and RS1226+ (full list in the specifications)
Module validated by Synology: memory from another brand can make the NAS unstable or prevent it from booting
On a DS925+, two 16 GB modules take the memory to its 32 GB maximum.

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Description

Synology · Reference D4ES03-16G

More room for your NAS,
same enclosure.

The DiskStation DS725+, DS925+ and DS1525+ ship with 4 or 8 GB of memory. This 16 GB DDR4 ECC module lets them run more applications and services at the same time.

  • 16 GBon a single module
  • 2slots on these NAS
  • 32 GBmaximum, two modules

What each NAS starts with

On the DiskStation models we offer, Synology provides two memory slots, only one of which is filled on delivery. The ceiling is the same on all of them: two 16 GB modules.

DS725+
4 GB fitted · 32 GB max
DS925+
4 GB fitted · 32 GB max
DS1525+
8 GB fitted · 32 GB max

To reach 32 GB, the original module makes way for a second D4ES03-16G. Check the exact name of your NAS in the list of compatible models before ordering: the DS224+ and DS423+, for example, use a different module.

The brand's other modules are in the RAM memory section, and the full range is on the Synology page.

Slots, fitted memory and maximum capacity: Synology specifications for each NAS and compatibility list for its DDR4 modules.

Technical specifications

Technical specifications
CompatibilitySynology RackStation NAS RS1226RP+, RS1226+, RS826RP+, RS826+, RS822RP+, RS822+, RS1221RP+ and RS1221+
ECC supportYes
Capacity16 GB
Number of modules1 module
Module capacity16 GB
Form factorSO-DIMM (short module)
DDR generationDDR4
Technical specifications (continued)
Buffered memory (registered)Unbuffered
Memory module type260-pin SO-DIMM
Product typeMemory (RAM)
Compatible machineServer and NAS
Compatible modelsSynology DiskStation NAS DS1825+, DS1825neo+, DS1525+, DS1525neo+, DS925+, DS925neo+, DS725+, DS725neo+, DS1823xs+, DS923+, DS723+, DS3622xs+, DS2422+, DS1522+, DS1821+, DS1621xs+, DS1621+ and DVA3221
PackagingSingle module
Warranty5 years

Specific references

EAN4711174726462
MPND4ES03-16G

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Frequently asked questions about this product

Is this module compatible with my Synology NAS?
Yes, if your NAS is on Synology's list. It is validated on models from series 21 to 26, including the DS925+, DS1825+, DS1525+, DS923+, DS1621+ and the RackStation RS1226+ or RS822+. The full list of models is given in the specifications of this page: check the exact name of your device there.
Can I install a memory module from another brand in my NAS?
Synology advises against it. The manufacturer states that a memory module from another brand can make the system unstable or prevent it from booting, and recommends installing only its own modules. This is a genuine Synology module, tested for the NAS on its compatibility list: the safe choice for a server that runs around the clock.
How far can I expand the memory of a DS925+?
The DS925+ ships with 4 GB of memory installed on one module, and it has two slots. Synology sets its maximum capacity at 32 GB, i.e. two 16 GB modules: to reach it, you install two D4ES03-16G in place of the original module. The D4ES03-16G is indeed on the list of modules Synology validates for this model.
What is ECC error correction for?
ECC memory (Error Correcting Code) automatically detects and corrects the small errors that can occur in data held in memory. On a NAS that stores the company's files and stays on day and night, it prevents a transient error from spreading to the stored data or crashing the system.
What is the difference with the D4ES03-8G module?
Both modules are of the same type, DDR4 ECC in SO-DIMM format. The D4ES03-16G provides 16 GB instead of 8, and Synology validates it on more models: in addition to series 22 to 26, common to both, it is also compatible with series 21, such as the DS1621+, DS1821+ or RS1221+, which the 8 GB version is not.
My DS224+ or DS423+ is not on the list: what should I choose?
This is not the right module for these models. The DS224+, DS225+, DS423+ and DS425+ use non-ECC DDR4 memory, and Synology pairs them with a different module, the D4NS01-4G. Before ordering, always check the exact name of your NAS in the list of compatible models: a module that is not on it may not be recognised.

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