Setting Up a CBT Exam Lab: Ratios, Network and Spares

Renting laptops for a CBT (Computer-Based Test) exam is the fastest way for organisers — school PPDB admission committees, BNSP/LSP certification bodies, universities, and agencies running CPNS civil-service tests — to source 100–500 units inside a short window without a purchase investment. At Arental, CBT rental packages start from Rp 50,000 per unit per day for the standard tier, already including a pre-installed lockdown browser, a venue site survey, a 60-minute invigilator briefing, a free 4% spare pool, and a handover certificate (BAST) per session. This guide is written from the organiser's side: how to calculate unit counts, the spec that is safe, the D-21 to D+1 deployment timeline, a 200-unit cost simulation, and an exam-day checklist — all based on a workflow already proven across hundreds of exam sessions.

Know Your Exam Type First: Volume and Lockdown Vary Enormously

The most common first-time committee mistake is assuming all CBT is the same. In reality, unit volume, lockdown browser type, and invigilation profile differ drastically between exam types — and those differences drive the laptop tier and the final cost.

Two practical implications. First, the lockdown type determines imaging effort: a light Education Office PPDB browser images quickly, while the BKN CAT system with video proctoring needs a higher unit tier so camera streaming does not throttle the CPU while the exam application runs. Second, the invigilator profile determines briefing depth: schoolteachers handling online PPDB for the first time need a one-page SOP and a WhatsApp escalation group, whereas BNSP assessors only need a platform orientation.

How Many Laptop Units Should You Rent?

The formula is simple, but it is often miscalculated because committees forget to split participants into sessions:

1. Seats per session = total participants ÷ number of sessions. CBT exams almost always run multi-session (2–3 sessions per day), so you do not need one laptop per participant. 2. Units to rent = seats per session + a 4% spare pool (1 spare per 25 active units).

Example: 480 PPDB participants, scheduled over 2 days with 2 sessions per day = 4 sessions. Seats per session = 480 ÷ 4 = 120. The 4% spare = 5 units. Total requirement = 125 units — not 480. At Arental the 4% spare pool is bundled free and kept on-site, so you still only pay for the 120 active units.

Mind the opposite direction too: splitting into too many sessions does shrink the unit count, but it stretches rental days and invigilator hours. For most school exams, 2 sessions per day is the balance point between unit cost and committee fatigue.

CBT Laptop Spec: The Safe Floor, and When to Step Up a Tier

For web-based CBT — the majority of providers today — the proven reliable minimum is: Intel Core i3 10th gen+ or AMD Ryzen 3 5300U, 8GB RAM, a 256GB SSD, a 14-inch anti-glare display, a healthy 6+ hour battery, and a 720p front camera for identity verification. Commonly deployed units: Lenovo ThinkPad T440/T460/T470, HP EliteBook 840 G3/G5, and Dell Latitude 5480/5490 — enterprise generations already proven for exam workloads. The full component-by-component spec table, including Windows versions and the lockdown profile, is on the CBT exam laptop rental page.

When should you step up a tier? Only if your exam uses intensive video proctoring — CPNS with the BKN CAT system, or international professional certification. In that scenario, camera + audio streaming runs in parallel with the exam application, and an older-generation i3 can stutter. The fix is stepping up to a ThinkPad T490/T14 with Wi-Fi 6. Conversely, renting the Heavy Proctoring tier for a light browser-based PPDB is pure waste: the exam application will never use the performance headroom, yet you pay Rp 30 thousand more per unit per day.

Deployment Timeline: From D-21 to D+1

The flow below is the standard workflow for a 200-unit multi-venue package — compress or relax it to match your scale:

• D-21 to D-14 — Site survey + spec confirmation. Technicians check power capacity per room, the LAN/Wi-Fi network, and desk layout at every venue. Output: a site survey report + a final spec sheet.
• D-13 to D-7 — Mass imaging + lockdown setup. Every unit is imaged at the Kebon Jeruk warehouse with the Windows profile the committee requires, then boot-tested into the exam portal one by one.
• D-6 to D-3 — Deployment to venues. Units arrive in boxes labelled by session/room, power strips and LAN are installed per desk, units are labelled per seat number, and the delivery handover certificate is signed per venue.
• D-2 to D-1 — Technical rehearsal + invigilator briefing. Every unit boots into lockdown and runs a 5-minute sample question set. Invigilators get a 60-minute briefing: the boot SOP, login, troubleshooting, escalation, and the spare-swap procedure.
• Exam day — Technicians on standby. A ratio of 1 technician per 100 units at the primary venue, with a replacement SLA of under 15 minutes for any problem unit.
• D+1 to D+3 — Collection + final handover. Units are collected against a serial-number checklist, and an audit summary report (sessions served, spares used, technical incidents) reaches the committee lead within 2 working days.

The lesson from hundreds of sessions: the most underrated phase is the D-1 technical rehearsal. Exams that fail almost never fail because of the laptops — they fail because the CBT server was never tested from the venue network, or because invigilators did not know the swap procedure. The rehearsal closes both gaps at once.

How Much Does Renting Laptops for a CBT Exam Cost? A 200-Unit Simulation

Arental's per-unit-per-day pricing already includes the lockdown profile, a LAN cable, an optional mouse, and technical support. The site survey, invigilator briefing, 4% spare pool, and per-session handover certificate are included too:

A concrete simulation — PPDB with 200 standard-tier units (Rp 50,000), a 4-day exam window, 2 sessions per day:

Rp 25,000 per participant — that is a number worth taking into a budget meeting, because it sits far below the cost of provisioning a permanent computer lab that only gets used a few weeks a year.

One trade-off that must enter your planning: order timing. Ordering at D-21 gets normal pricing and custom lockdown options. An order at D-7 or later can still be accommodated, but with a spec-fixed package and a 15–25% rush fee — on the simulation above, that means an extra Rp 6–10 million. For PPDB, whose schedule is fixed by the regional Education Office early in the year, there is no reason to pay that lateness premium. For government and institutional committees, every transaction is supported by VAT e-invoicing (e-faktur PPN) and Article 23 withholding tax (PPh 23) handling as your treasurer requires.

Lockdown Browsers and Exam Security: What to Demand from Your Vendor

Exam integrity rests on two things: a correct lockdown and tested units. At a minimum, the vendor must pre-image whatever lockdown the committee specifies — Safe Exam Browser for Moodle, the dedicated LSP/BNSP browser, the BKN CAT system, or the Education Office PPDB app — and then disable the common cheating vectors: USB autoplay, user switching, the Task Manager shortcut, and Cortana. Every unit must be boot-tested into its lockdown profile before delivery — not just a sample.

On physical risk, ask for a written clause. Arental's standard: minor damage (scratches, screen scuffs) is covered by the package insurance at no charge; major damage (cracked LCD, motherboard failure) is borne by the committee at vendor part prices with a transparent price list provided up front; a lost unit is charged at market value. Three-year statistics: major damage under 0.3% and lost units under 0.05% — provided invigilators run a per-session unit roll-call (start + finish).

The Committee Checklist Before Exam Day

• Confirm the final participant count and session split to the vendor no later than D-7.
• Make sure the CBT server/portal has been tested from the venue network during the rehearsal, not just from the office.
• Appoint 1 technical PIC per room who holds the WhatsApp escalation group.
• Print the one-page invigilator SOP: boot, login, restarting the application, the swap procedure.
• Agree where the spare units are stored and who is authorised to approve a swap.
• Schedule a unit roll-call per session (start + finish) for early loss detection.
• Keep the delivery handover certificate — it is the document used for internal audit and the D+1 reconciliation.

If your exam sits inside a larger production — certification alongside a conference, or mass recruitment with an assessment series — the management pattern resembles event device procurement; our guide to laptop rental for event organizers covers that side in depth. For regular training classes outside the exam season, see also laptop rental for employee training and onboarding.

Frequently Asked Questions

What is the minimum lead time to rent 200 CBT laptops?

10–14 working days for a 200-unit multi-venue package. For PPDB, whose schedule is fixed by the Education Office, ordering at D-21 is ideal. An order at D-7 or later can still be served with a spec-fixed package and a 15–25% rush fee.

Does the committee or the vendor install the exam application?

The vendor. All units are mass-imaged at the warehouse with the lockdown browser the committee specifies, then boot-tested into the exam portal one by one before dispatch. The committee only needs to supply the installer/application access and test credentials.

What happens if a laptop fails in the middle of an exam session?

The invigilator reports it via the venue WhatsApp group, and the unit is swapped from the on-site spare pool with a sub-15-minute SLA. The standard ratio is 1 technician per 100 units on standby at the primary venue, with remote support for distant venues.

Can exams outside Greater Jakarta be served?

Yes. Bandung, Surabaya, Yogyakarta, and Semarang are served via logistics partners with a lead time of +2–4 days versus Greater Jakarta — the pattern commonly used for multi-location CPNS tests.

What documents does the committee receive?

A handover certificate (BAST) per venue for delivery and collection, an audit summary report (sessions served, spares used, technical incidents) within 2 working days after the exam, plus VAT e-invoices for institutional finance requirements.

Preparing a CBT exam in the coming months? Contact the Arental team via WhatsApp with four basics: the exam type, estimated participant count, exam date, and venue. Our team will help calculate unit counts, recommend a tier, and build the deployment timeline from site survey to the final handover certificate — or start from the contact page to request a formal quotation.