Prime Big Deal Days Complete Builds, Priced Part by Part

Why a system page, and what it will not do

Every other page in this event sells one item. This one sells systems: a network-attached storage box with a drive in every bay, a rack-mount disk shelf filled to capacity, the frame, power and network link of a homelab rack, and the two-tier storage of an AI workstation. These are the largest purchases anyone makes in our categories, and they are where a single headline discount matters least - a system is six or twenty-six prices, and the event moves each of them separately or not at all.

Nothing on this page is a new calculation. The totals come from the same basket engine as our fill pages, and each part is chosen by the picker its own standing page already runs: the fill pages choose the NAS drives, the disk-shelf pages choose the shelf drives, the rack and UPS pages choose the frame and the power, and the networking pages choose the link. What this page adds is the assembly, the verdict on every part, and a proof that each assembly physically works.

Every build has two totals. Best value uses the drive with the lowest cost per terabyte, which is usually the largest drive and the largest bill. Lowest outlay uses the cheapest qualifying drive by unit price - the smallest cheque that completes the same system. Both are real answers to different questions, and neither is hidden behind the other.

Synology DiskStation DS225+ 2-Bay + 2 drives

2-bay NAS filled with new, CMR-verified 3.5-inch SATA drives. The machine's own trays ship with it, so no caddy line is needed.

Best-value total: $1,423.07 · Lowest outlay: $633.27

Fill the DiskStation DS225+ 2-Bay

TerraMaster F4-425 Plus 4-Bay + 4 drives

4-bay NAS filled with new, CMR-verified 3.5-inch SATA drives. The machine's own trays ship with it, so no caddy line is needed.

Best-value total: $2,809.95 · Lowest outlay: $1,230.35

Fill the F4-425 Plus 4-Bay

Synology DiskStation DS1525+ 5-Bay + 5 drives

5-bay NAS filled with new, CMR-verified 3.5-inch SATA drives. The machine's own trays ship with it, so no caddy line is needed.

Best-value total: $4,009.94 · Lowest outlay: $2,035.44

Fill the DiskStation DS1525+ 5-Bay

QNAP TS-664-8G 6-Bay + 6 drives

6-bay NAS filled with new, CMR-verified 3.5-inch SATA drives. The machine's own trays ship with it, so no caddy line is needed.

Best-value total: $3,951.43 · Lowest outlay: $1,582.03

Fill the TS-664-8G 6-Bay

HP D2700 disk shelf + 25 drives

A bare 25-bay 2.5" SAS shelf filled to every bay. Its SAS generation comes from HP's own page title; every drive matches it.

Best-value total: $1,655.50 (partial - see the required unpriced lines) · Lowest outlay: $1,655.50

Today the best-value basket is also the lowest outlay: the same parts win on cost per terabyte and on unit price, so there is one list, not two.

HP D2700 · Every JBOD shelf · SAS cables

Homelab rack: frame, PDU, UPS and a 10GbE link

The mounting, power and network half of a homelab rack, from the rack, UPS and networking clusters. The servers themselves are yours; the two network cards need a free PCIe slot in each machine.

Best-value total: $1,118.83 · Lowest outlay: $445.83

Racks · UPS & PDU event page · Networking event page · Rack event page

AI workstation storage: working set + archive

The two-tier split from our AI storage pages: a 4TB-class NVMe working drive for the models you load this week, and the cheapest CMR terabytes for the library. Storage only - we track no GPUs, processors or boards, so none is priced and no system total is implied.

Best-value total: $1,049.98 · Lowest outlay: $393.48

AI storage · Model library calculator · Budget inference rig

How each build is assembled, and the rules it has to pass

The NAS builds use machines whose makers publish a bay specification naming 3.5-inch SATA hard drives, one per bay count, the cheapest in stock. A machine with a bay count but no published bay form factor is not used, because a basket that assumed the bay type would be an inference dressed as a specification. The drives are new, CMR-verified, 3.5-inch SATA - the same rule our fill pages run, with the form factor pinned. A NAS ships with its own drive trays, so no caddy line is needed.

The disk-shelf build is the cheapest bare shelf whose maker's own text states its SAS generation. Every drive in it matches that generation and the shelf's form factor. A shelf sold bare needs trays, and a JBOD needs an external host bus adapter and a cable before it does anything; where we hold no listing we can match to the shelf, those parts are named as required, unpriced lines, and the total is marked partial rather than silently short.

The homelab rack uses a 4-post frame whose listed depth reaches the minimum of Dell's own sliding-rail range, so a rail-mounted server can go in it; the lowest-outlay version uses the cheapest frame of any post type and says what that rules out. The power distribution unit is a 1U horizontal unit that mounts in the rack's own rails. The UPS is a tower unit with stated pure sine output - tower on purpose, because no rackmount UPS we track states its depth. The PDU and UPS are priced side by side, not chained together: how they connect is an electrical question this site does not answer. The network link is two cards and one cable of the same connector family.

The AI workstation storage follows our AI storage pages' two-tier split: an M.2 NVMe drive for the working set and the cheapest CMR terabytes for the library. It is storage only. We track no GPUs, processors or boards, and no figure here implies a system total.

What is not cartable, listed plainly

Some parts of a complete system have no listing we can price. They are shown here so the build is complete, and they are never cartable and never inside any total on this page.

Every server platform in our build guides has a live chassis listing today, so no chassis is priced as a band.

Required parts with no verified listing

• Drive trays / carriers for the D2700 x25 (HP D2700 disk shelf + 25 drives) - Required - the shelf is sold bare and trays are shelf-specific. We hold no verified tray listing for this model, so they are named here and priced nowhere.
• External SAS host bus adapter x1 (HP D2700 disk shelf + 25 drives) - Required - a JBOD has no controller of its own. Every HBA we track is an internal-port card, so none can be put in this basket.
• External SAS cable x1 (HP D2700 disk shelf + 25 drives) - Required - but HP's documentation we could read does not state the shelf's external connector, so we cannot match a cable to it.

Manufacturer-listed drives with no retail price

10 of the largest enterprise SSDs are listed by their makers but sold at no retail price we can measure. They appear, without a price, on the enterprise flash page, and in no basket here.

The basket question June could not answer

Our June 2026 retrospective measured categories, not baskets. On the matched-model index, where each listing is compared only with its own earlier price, the categories we could measure did not move in any measurable way across that event (NAS HDD +0.17%, Enterprise HDD +0.93%, SSD (all interfaces) +0.00%, External HDD +0.00%). That is a finding about categories.

A basket is not a category. A basket total can move when a single component hits its own low even if its category index is flat - one drive in a twelve-drive build dropping to its recorded low changes the total by twelve times that drop, and the category it belongs to may not register it at all. The reverse is also true: a flat category can hide a component that has risen.

So we will measure basket totals across this event - the builds on this page, part by part, against each part's own record - and publish the result afterwards, the same way we published June's. We make no prediction about what that measurement will show.

Frequently asked questions