You have bought a powerful graphics card or are planning an upgrade, and now you face the question that confuses many builders: is an 850W power supply enough, or do you need 1000W? A wrong choice here does not show up on installation day. It shows up later as sudden shutdowns mid-game, extra heat and fan noise during the Iraqi summer, or a damaged component after the first fluctuation in generator power. The power supply feeds every other part of your PC, so it deserves an informed choice rather than simply the biggest number printed on the box. In this guide we explain how to work out what you actually need, then recommend power supplies available now, organised by the type of graphics card you own.
Criteria for choosing the right wattage
- Start with the GPU maker's recommendation: NVIDIA recommends a 1000W power supply for the RTX 5090, 850W for the RTX 5080 and 850W for the reference RTX 4090, while MSI's guides suggest around 750W for the RTX 5070 Ti in typical use. These figures are for the whole system, not the card alone.
- Factor in the CPU: High-end processors such as Core i9 and Ryzen 9 push the requirement up a full tier, which is why manufacturer guides advise moving to the next tier when pairing a strong GPU with a strong CPU or when overclocking.
- ATX 3.0 or ATX 3.1: This means the unit is designed to handle the momentary power spikes of modern graphics cards, and it usually ships with a native 16-pin cable (12VHPWR or 12V-2x6), so no adapters are needed.
- 80 Plus efficiency rating: The higher you go, from Bronze to Gold to Platinum, the less energy is wasted as heat inside the case, which matters in a room that gets hot in summer.
- Modular design: A fully modular unit lets you connect only the cables you need, improving airflow and reducing dust build-up around loose cables.
- Brand and protections: Choose a well-known brand with the essential protections against over-voltage, over-current, short circuits and over-temperature, as these are the first line of defence against unstable power.
For the RTX 5090 or a strong GPU with a top-tier CPU: Thermalright SP1000
If your build includes a flagship card such as the RTX 5090, or a partner RTX 4090 model that calls for more power, alongside a strong processor, you are firmly in 1000W territory. The Thermalright SP1000 attracts the most interest from our store visitors in this class, and it carries an 80 Plus Platinum rating, meaning higher efficiency than Gold and less heat leaking into the case. Retailer listings describe it as fully modular and compatible with ATX 3.1 and PCIe 5.1, specifications that suit current-generation cards. It suits anyone who wants Platinum efficiency at 1000W at a reasonable cost.
A Gold-rated 1000W alternative: Cooler Master ELITE 1000W
Cooler Master is a well-known name in cooling and power supplies, and the ELITE 1000W comes with an 80 Plus Gold rating and a fully modular design, as its name indicates. It is a balanced choice for anyone with a powerful card who wants a comfortable power margin for future upgrades, from a brand whose support and cables are easy to find.
For the newest generation with ATX 3.1: Segotep GM1000W
This unit's name explicitly states ATX 3.1 and PCIe 5.1 compatibility, along with 1000W capacity, an 80 Plus Gold rating and a fully modular design. That makes it a good fit for RTX 50 cards that use the 16-pin connector, and it comes in both black and white for builders who want a matching colour theme.
850W with a premium touch: ASUS ROG THOR 850W Platinum II
For RTX 5080 owners and anyone building a premium system, the ROG THOR series represents the top tier of ASUS power supplies. According to its name, this version offers 850W, an 80 Plus Platinum rating, a fully modular design and PCIe 5.0 support. It is a choice for those who want the highest quality at 850W and for whom budget is not the first priority.
Affordable and balanced 850W: Cooler Master ELITE 850W
If your card is an RTX 5080, or an RTX 5070 Ti paired with a strong CPU, 850W is the sweet spot between safety and cost. The Cooler Master ELITE 850W offers an 80 Plus Gold rating and a fully modular design, and it is among the units in this class that attract the most interest from our store visitors.
Platinum efficiency at 850W: Thermalright SP850
The smaller sibling of the SP1000, with the same 80 Plus Platinum rating. A smart choice for anyone who wants higher efficiency and less heat at 850W, especially if the PC runs for long hours every day in a warm room.
From ASUS with PCIe 5.0 support: ASUS Prime AP-850G
The Prime series is the practical line from ASUS, and according to its name this model offers 850W, an 80 Plus Gold rating, a fully modular design and PCIe 5.0 support. It suits those who prefer to stay within the ASUS ecosystem alongside a motherboard or graphics card from the same company.
For the mid-range: ASUS Prime AP-750G
Not every PC needs 850W. If your card is an RTX 5070 Ti with a mid-range CPU, or a less power-hungry card, a Gold-rated 750W unit is usually enough and saves part of your budget for another component. According to its name, this model has a fully modular design and PCIe 5.0 support.
Common mistakes when buying a power supply
- Relying on the number alone: A 1000W unit of unknown origin can be more dangerous than an 850W unit from a known brand, because internal quality and protections matter more than the printed number.
- Unjustified overkill: Buying 1000W for a mid-range card adds no performance; it only takes budget that could have gone to a better GPU or CPU.
- Mixing modular cables: Never use cables from an old power supply with a new one, even from the same brand, because the pin layout on the PSU side differs between models and can damage components.
- Neglecting the 16-pin connector: Push the connector in all the way and avoid bending the cable sharply near the card, since an incomplete connection is a known cause of connector overheating.
- Ignoring unstable electricity: Frequent switching between grid power and the generator stresses any power supply, and a good UPS or voltage stabiliser protects the whole PC.
- Neglecting dust: Clean the PSU fan and air intake every few months, and do not place the case directly on the floor or on a carpet.
Frequently asked questions
Is an 850W power supply enough for an RTX 5080 or RTX 4090?
Yes, in most cases, since that is the capacity NVIDIA recommends for the full system with either card. However, if your CPU is top-tier, or your card is a partner model whose manual calls for more power, moving to 1000W is the safer decision.
Does a 1000W power supply use more electricity than an 850W one?
No. The rated number is the maximum the unit can deliver, not what it actually draws. The PC draws only what its components need, and the real difference in consumption comes from efficiency, so a more efficient unit slightly eases the load on your generator subscription for the same usage.
What is the difference between 80 Plus Gold and 80 Plus Platinum, and is it worth it?
Platinum means higher efficiency than Gold, so less energy is lost as heat. The difference on the electricity bill is small, but it shows in the unit's temperature and fan noise, which matters to anyone running a PC for long hours in the Iraqi summer.
Do I need an ATX 3.1 power supply for RTX 50 cards?
It is not strictly required, but it is the preferred choice: the ATX 3.x standard is designed to handle the momentary power spikes of modern cards and provides a native 16-pin cable instead of adapters. MSI explicitly recommends ATX 3.1 or PCIe 5.1 units for this reason.
Can a power supply handle power cuts and generator fluctuations?
A good unit includes protection against over-voltage, under-voltage and short circuits, but it is not a substitute for a UPS or voltage stabiliser. If the power in your area is unstable, make a suitably rated UPS part of your build budget.
How can I make sure a power supply is genuine?
Check the side label showing the model and serial number, match the efficiency rating printed on the box with the label, and make sure the packaging is intact. A strikingly low price for a well-known brand is a sign to be cautious.
Can I use a 750W power supply with an RTX 5070 Ti?
Yes, with a mid-range CPU, as that is the capacity MSI's guides suggest for typical use with this card. With a top-tier CPU or when overclocking, choosing 850W gives you a more comfortable margin.
Conclusion and final recommendation
For RTX 5090 owners or a flagship build with a strong CPU: 1000W without hesitation, with the Thermalright SP1000 as the most balanced choice thanks to Platinum efficiency, and the Cooler Master ELITE 1000W and Segotep GM1000W as excellent alternatives. For RTX 5080 or RTX 4090 owners with a mid-range CPU: the 850W class, from the affordable Cooler Master ELITE 850W to the premium ROG THOR. For mid-range builds: the ASUS Prime AP-750G is enough and saves budget. Pick the right unit and order it now: you pay cash on delivery, delivery covers every governorate in Iraq, and you can ask us on WhatsApp before ordering about compatibility with your card or about the warranty.
