Mk IV
The deck most of our customers should buy, and the one we know best: four chassis revisions, 6,180 units, and a service history long enough that we can tell you what fails on it and when.
Section 1 · Ordering
Part numbers and availability
Lead times are working days from a confirmed order, measured against what we actually shipped last quarter. Prices in credits at the works, excluding duty.
| Part no. | Configuration | Price | Availability | Lead time |
|---|---|---|---|---|
| CS-4D-032 | Mk IV, 32 MB fitted | 6,900 cr | In stock | 3 working days |
| CS-4D-064 | Mk IV, 64 MB fitted | 9,400 cr | In stock | 3 working days |
| CS-4D-032-S | Mk IV, 32 MB, sealed chassis (Mk III seal spec) | 7,650 cr | Built to order | 15 working days |
| CS-4D-000 | Mk IV, no memory fitted (bench/OEM) | 4,900 cr | Built to order | 10 working days |
| CS-4C-032-R | Mk IV rev C, refurbished, 32 MB | 4,200 cr | Stock varies | Ask the desk |
Ordering
Through the desk at cybrscape.com/desk, 06:00 to 20:00, six days. Quote the part number and your resident load. Nothing on this site takes a payment.
Fleet orders
Six or more decks: matched revision, sequential serials, and a field-exchange contract quoted with them. Ask for terms.
Documentation
The operator manual is printed and ships in the box. The service manual and test card are issued to authorised benches, ours and anyone else’s who asks properly.
Section 2 · Layout
Fourteen M3 fasteners and one driver
The rule since the Mk II: no serviceable part may require the removal of another serviceable part. On a Mk IV the memory board comes out without touching the interface stack, and the net module comes out without touching either.
Section 3 · Memory
Where the 32 megabytes go
People are most often surprised by this figure. Of a 32 MB Mk IV, 12.0 MB is committed before you load a single program: firmware and the interface layer take 3.0, scratch and cache take 5.0, and the ICE reserve takes a fixed 4.0 that cannot be paged out. The fixed reserve is deliberate: it is why a Sentry waking up does not cost you your Barrier.
Scratch and cache are shared and can be squeezed, but squeezing them is how people end up with a deck that stalls on a link hiccup. We size the six resident slots at 3.0 MB nominal apiece, which is the median resident program on the decks that come through our own service department.
A 64 MB Mk IV changes one number: the space for warez goes from 20.0 MB to 52.0 MB. Firmware, ICE and scratch are identical in both, so doubling the memory gives you 2.6 times the room for programs.
Section 4 · Specification
Full specification, CS-4D
Measured at Bay 4 on production hardware at 22 °C with a cell above 90 %. Where a figure depends on conditions, the conditions are in the row.
| Fitted memory | 32 MB (CS-4D-032) or 64 MB (CS-4D-064) |
|---|---|
| Maximum memory | 64 MB. One board, no stacking |
| Memory type | Graded matched stack, 14 ns, socketed |
| Available to warez | 20.0 MB of a 32 MB deck, nominal: 18.0 in the six slots, 2.0 unallocated. See the budget. |
| Resident warez slots | 6 |
| ICE reserve | 4.0 MB, fixed. Barrier, Ward and Sentry cannot be paged out |
| Scratch & cache | 5.0 MB, shared |
| Cache persistence | Held across a cold jack-out; cleared on cell change |
| Jacks | 2 (primary, secondary) |
|---|---|
| Jack standard | Type-4 twist-lock, 2.4 mm |
| Concurrent operators | 1. The second jack is for instrumentation. |
| Response latency | 14 ms, jack to net, measured at the works |
| Trace exposure | Not a deck specification. Do not let anyone sell you one. |
| Link rate | 180 Mb/s sustained, 240 Mb/s burst |
|---|---|
| Physical | Twin coax or single fibre, field-swappable module |
| Session hold | 40 minutes on link loss before the cache is dropped |
| Dimensions | 298 × 208 × 48 mm |
|---|---|
| Mass | 2.2 kg with cell and 32 MB fitted |
| Chassis | Machined 6082 aluminium, anodised, replaceable corner blocks |
| Fasteners | 14, all M3 hex. One driver opens the whole deck |
| Cell | CS-AX-204, 7 hours nominal, hot-swappable with cache held |
| Ingress | Splash and dust. For the Mk III seal spec, order CS-4D-032-S. |
| Operating range | −5 to 42 °C. Derates above 38 °C and tells you it is doing so. |
| In the box | Deck, one cell, 2 m jack lead (CS-AX-231), printed manual, calibration card |
|---|---|
| Not in the box | Warez. We do not sell programs. |
| Warranty | 36 months, parts and labour, transferable with the deck |
| Service parts held | Until 2039 at the earliest, ten years past withdrawal |
Section 5 · Revisions
Four revisions, and what each one was for
Each revision answers something that kept coming back to the Fenn Street bench. The change column says what it was.
| Rev | Year | Change | Status |
|---|---|---|---|
| A | 2025 | First production. 1,100 units. | Superseded |
| B | 2026 | Corner blocks made replaceable after field reports of drop damage writing off good chassis. | Superseded |
| C | 2027 | Memory socket retention revised; 64 MB boards were walking loose under vibration. Free retrofit, 340 units done. | Serviced |
| D | 2028 | Cell contacts gold-plated; thermal derate curve made visible to the operator. Current. | Shipping |
Known limitations
If one of these matters to you, buy something else, including a Nitrosoft if that is what fits.
- It is not sealed to the Mk III standard. Splash and dust only. If you work in weather, order CS-4D-032-S at 7,650 cr or buy a Mk III and accept the slower link.
- It derates above 38 °C and shows the derate on screen. Some operators find that insulting.
- 64 MB is the ceiling. One board, no stacking.
- The second jack is instrumentation. It does not take a second operator, and a deck sold to you as one that does did not come from us.
- Revision A and B chassis cannot take the revision C socket retention without a new processor carrier, CS-SP-430, 140 cr fitted. The retention retrofit itself remains free.
Section 6 · Warranty & service
Thirty-six months, transferable, and parts until 2039 at the earliest
The warranty runs from the date on the signed test card that ships with the deck, covers parts and labour, and transfers with the deck when you sell it. Service parts for the Mk IV are held for ten years after the mark is withdrawn, and it has not been withdrawn.
| Level | Code | Turnaround | Charge |
|---|---|---|---|
| Bench | CS-SV-B | 10 working days | Diagnosis 40 cr, credited against the repair |
| Priority | CS-SV-P | 3 working days | 180 cr per docket, plus parts |
| Field exchange | CS-SV-X | Next working day, replacement deck | Contract, from 1,400 cr per deck per year |
Full service terms, the docket process and our turnaround figures →