When you are putting together a new desktop, the decision often stalls at a single confusing question: is an 850W power supply enough, or should you step up to 1000W? The gap between those two numbers is not just a figure on a label. It affects how stable the system is under heavy load, how hot it runs inside, how loud the fan gets, and whether it can absorb a graphics card upgrade a year or two from now. This guide sets out clear criteria to settle the choice, walks through power supplies we actually have in stock in each class, and closes with common mistakes and the questions Iraqi buyers ask before paying.
How to choose a power supply
Before comparing the two numbers, lock down the following criteria, because they settle the decision faster than any price comparison:
- Real load, not peak rating: the two biggest power draws in a build are the graphics card and the CPU. The motherboard, memory, drives and fans take a far smaller share. Add up the manufacturer-stated figures for those two parts, then leave headroom for the rest.
- Comfortable operating margin: a power supply is most efficient and quietest when the load sits near half of its rated capacity. Avoid a unit that runs at the edge of its rating all day long.
- Transient spikes: modern graphics cards pull very short bursts well above their usual draw. A unit that cannot absorb them may shut the machine down mid-game even though the average draw looks safe.
- 80 PLUS efficiency rating: Gold means roughly 90% efficiency at half load, and Platinum sits above it. Higher efficiency means less wasted energy and less heat trapped inside the case.
- Standard and connectors: the ATX 3.1 standard with the 12V-2x6 connector used by PCIe 5.x carries up to 600W over a single cable and is designed to handle transient spikes. If a modern graphics card is in your plans, this matters.
- Full modular cabling: you attach only the cables you need, which keeps the case tidy, improves airflow and makes it easy to swap a single cable later.
- Built-in protections: over-current, over-voltage, over-temperature and short-circuit protection are not luxuries, especially with unstable mains power and frequent switching between the grid and a generator.
A first conclusion: if your build is mid-range to strong and no major upgrade is planned soon, 850W is a balanced, comfortable choice. If you are building a high-performance machine or want the upgrade door open for years, 1000W buys you a wider margin for a smaller price gap than most people expect.
ASUS ROG THOR 850W Platinum II
The premium option at the 850W tier: 80 PLUS Platinum efficiency means less heat and less wasted power, fully modular cabling lets you connect only what you need, and PCIe 5.0 connector support covers modern cards. The black finish suits builds people actually look into.
ASUS Prime AP-850G
An 850W unit rated 80 PLUS Gold with full modular cabling and PCIe 5.0 support, offering the combination most buyers ask for: a current standard, high efficiency and clean cable routing without moving into the most expensive tier. A good fit for a strong gaming build or a mid-range workstation.
Cooler Master ELITE 850W
A well-known name in cooling and cases, and this unit pairs an 80 Gold rating with full modular cabling in a plain black body. A practical pick for anyone who wants 850W at Gold efficiency and tidy internal routing without overthinking the decision.
Thermalright SP850
Thermalright brings 80 PLUS Platinum efficiency to 850 watts here, a level that used to be reserved for pricier tiers. If your first priority is efficiency and lower temperatures inside the case, this black unit deserves a serious look.
Segotep GM1000W
This is where we move into the 1000W class: an 80 PLUS Gold rating and full modular cabling, with support for the ATX 3.1 standard and the PCIe 5.1 connector. That compatibility in particular makes it ready for modern graphics cards and their transient spikes, and it comes in black and white.
Cooler Master ELITE 1000W
The higher-capacity member of the ELITE family: a full kilowatt at an 80 Gold rating with full modular cabling. It suits anyone moving up from 850W for a wider future upgrade margin while keeping a consistent all-black look inside the case.
Thermalright SP1000
The bigger sibling of the SP850, rated at 1000 watts with 80 PLUS Platinum efficiency. Combining high capacity with Platinum efficiency means the unit sits in a very comfortable part of its load curve, so it stays cooler and quieter through long gaming sessions.
Common mistakes when picking a power supply
- Judging by wattage alone: an unknown 1000W unit can be worse than a trusted 850W one. Efficiency rating, protections and component quality come before the number.
- Sizing right at the limit: calculating your draw precisely and then buying a unit that exactly matches it means running at full tilt all the time, which brings a louder fan and a shorter life.
- Ignoring connector compatibility: buying a modern graphics card and then discovering your unit needs a stack of adapters is a common and frustrating problem. Check the connectors before you order.
- Neglecting cable management: tangled cables choke airflow and raise temperatures across every component, which is exactly where full modular cabling pays off.
- Carrying a very old unit into a new build: capacitors age over the years and real capacity drops, which produces sudden shutdowns that are hard to explain.
Frequently asked questions
Does a 1000W unit use more electricity than an 850W one?
No. The number printed on the box is the maximum the unit can deliver, not what it constantly draws. The system pulls only what it needs, and the larger unit may even be more economical because it operates at a better efficiency point.
What is the practical difference between Gold and Platinum?
The difference is how much energy turns into heat instead of reaching your components. Platinum is more efficient than Gold, and in practice that means less heat inside the case and less noise. The effect on your electricity bill is small, but the difference in heat and quietness is noticeable.
Do I really need ATX 3.1 and PCIe 5.1?
If you are going to run a modern high-performance graphics card, yes, because those standards were designed to handle transient spikes and deliver power over a single cable. With an older mid-range card, earlier standards do the job fine.
Is full modular cabling worth the price difference?
In most cases, yes. Connecting only the cables you need leaves more room behind the motherboard tray and improves airflow, and it makes maintenance and upgrades easier later without stripping the whole build down.
How long does a power supply last, and when should I replace it?
A good unit serves for many years if it runs within a comfortable margin in a clean environment. Replace it when you see sudden shutdowns under heavy load, hear crackling, notice an unusual smell, or when you move to a far more demanding graphics card.
Can I run a powerful graphics card on an 850W unit?
In many cases yes, provided the unit is from a trusted tier with a good efficiency rating and the right connectors. But if you are pairing it with a power-hungry CPU and planning an upgrade, stepping up to 1000W is the more relaxing decision.
Practical takeaway
Choose 850W if your build is balanced and no major upgrade is coming soon, and choose 1000W if you are building for high performance or want room for a stronger graphics card later. In both cases, put the efficiency rating, the protections and connector compatibility ahead of the number printed in bold. Every unit listed above is available from us with delivery to all governorates of Iraq and cash on delivery, so you can inspect the part in your hands before you pay.
