--- product_id: 2855239 title: "Coolmax LCD Power Supply Tester PS-228" brand: "coolmax" price: "€ 4.41" currency: EUR in_stock: false reviews_count: 8 url: https://www.desertcart.gr/products/2855239-coolmax-lcd-power-supply-tester-ps-228 store_origin: GR region: Greece --- # Accurate Readings ±0.1V Large LCD Display 8-pin PCIe Connector Coolmax LCD Power Supply Tester PS-228 **Brand:** coolmax **Price:** € 4.41 **Availability:** ❌ Out of Stock ## Summary > 🔧 Power Up Your Diagnostics with Precision! ## Quick Answers - **What is this?** Coolmax LCD Power Supply Tester PS-228 by coolmax - **How much does it cost?** € 4.41 with free shipping - **Is it available?** Currently out of stock - **Where can I buy it?** [www.desertcart.gr](https://www.desertcart.gr/products/2855239-coolmax-lcd-power-supply-tester-ps-228) ## Best For - coolmax enthusiasts ## Why This Product - Trusted coolmax brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **💡 Bright & Clear:** Large, backlit LCD display for easy visibility in any lighting. - • **⚙️ Next-Gen Ready:** Includes the latest 8-pin PCI-Express connector for modern setups. - • **🔍 Precision Testing:** Experience accurate diagnostics with readings up to ±0.1V. - • **🔗 Versatile Compatibility:** Works seamlessly with both 20-pin and 24-pin PSUs. - • **🛠️ User-Friendly Design:** The simplest way to troubleshoot your PC power supply issues. ## Overview The LCD Power Supply Tester PS-228 is a cutting-edge tool designed for PC enthusiasts and professionals alike. It features a large, backlit LCD display for clear readings, compatibility with both 20-pin and 24-pin power supply units, and introduces an 8-pin PCI-Express connector. With its ability to provide accurate voltage readings up to ±0.1V, this tester is the ultimate solution for diagnosing and troubleshooting power supply issues efficiently. ## Description Coolmax Technology, Inc PS-228 Device Tester 14912 885 Review: Works well - valuable troubleshooting tool - I purchased this because I was having some strange computer problems and suspected the power supply. I got this one through desertcart.com because it was half the price of the identical unit at the local branch of a major computer parts chain. I won't go into operation and use of the unit because other reviewers (especially P.S. and R.W.) have already provided great detail. If you are troubleshooting a modern desktop computer power supply (ATX style) or an older AT style, you must have one of these. It is about as easy as it can get to operate: connect the motherboard and CPU power plugs to the tool, and disk drive and SATA power plugs if you want to test power for those as well. Then press and hold the button and read the display. One thing that is rarely mentioned is that the power supply must have correct load impedances attached before it can operate at all. That is a characteristic of all switching power supplies, not just these. A switching power supply is not like an older analog power supply. If you disconnect it from the motherboard and try to measure output voltages, the power supply probably will not be operating. This tester provides the correct loads and makes the measurements for you. Another set of measurements it makes are critical time intervals during start-up, and the regular "power OK" signal that has timing and level requirements. Without this tool, you would also need an oscilloscope for those measurements. I have not had any physical problems such as those shown in user photos (end caps coming off, for example.) The only complaint I gave is the labeling. The case is black plastic, and all of the legends and markings are just raised black-on-black lettering. (User photos here show white lettering, but mine looks like the primary product photo - just all black.) It makes things hard to read, especially for eyes that are more than six decades old. I know there are ways to make the letters more visible, but a brighter light was more convenient. I highly recommend this if you are working on desktop computer equipment. Review: Great for testing power supplies - even ones that appear "OK" - This is wonderful for an instantaneous test of power supplies, to know if there is high or low voltage or a completely bad one. I work in a computer shop and have used this no less than 100 times for testing power supplies. There are a few cons of this product however to be aware of. 1. There isn't much documentation for instance it gives you a PG level, but no where does it tell you what this is. 2. The ends of the unit come off fairly easy where the plastic clips into the metal casing. It connects and tests 20/24 pin Motherboard connectors, 4 pin, and 8 pin EPS CPU connectors. SATA, Molex, and floppy connections, PCI-E 6 & 8 Pin connections. Good product overall with just the minor issues noted above. Would recommend to others. ## Features - Features Large, backlit LCD display - Compatible with 20-pin and 24-pin PSUs - Introduces the new 8-pin PCI-Express connector - The easiest method to accurately test or diagnose faults with your PC Power Supply Unit - Accurate readings up to +/- 0.1 V ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B002R06PGE | | Best Sellers Rank | #11,491 in Computer Power Supplies | | Brand | COOLMAX | | Brand Name | COOLMAX | | Compatible Devices | Personal Computer | | Customer Reviews | 4.1 out of 5 stars 115 Reviews | | Global Trade Identification Number | 00132018316849 | | Item Dimensions | 2.76 x 2.36 x 0.39 inches | | Item Weight | 4 ounces | | Item dimensions L x W x H | 2.76 x 2.36 x 0.39 inches | | Manufacturer | CoolMax USA | | Model | PS-228 | | Part Number | PS-228 | | Power Source | Battery Powered | | UPC | 191120085449 895963149121 172302774740 918510770071 132018316849 | ## Images ![Coolmax LCD Power Supply Tester PS-228 - Image 1](https://m.media-amazon.com/images/I/91JgpONXEML.jpg) ![Coolmax LCD Power Supply Tester PS-228 - Image 2](https://m.media-amazon.com/images/I/91Ma3qCA-mL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Works well - valuable troubleshooting tool *by G***E on October 20, 2011* I purchased this because I was having some strange computer problems and suspected the power supply. I got this one through Amazon.com because it was half the price of the identical unit at the local branch of a major computer parts chain. I won't go into operation and use of the unit because other reviewers (especially P.S. and R.W.) have already provided great detail. If you are troubleshooting a modern desktop computer power supply (ATX style) or an older AT style, you must have one of these. It is about as easy as it can get to operate: connect the motherboard and CPU power plugs to the tool, and disk drive and SATA power plugs if you want to test power for those as well. Then press and hold the button and read the display. One thing that is rarely mentioned is that the power supply must have correct load impedances attached before it can operate at all. That is a characteristic of all switching power supplies, not just these. A switching power supply is not like an older analog power supply. If you disconnect it from the motherboard and try to measure output voltages, the power supply probably will not be operating. This tester provides the correct loads and makes the measurements for you. Another set of measurements it makes are critical time intervals during start-up, and the regular "power OK" signal that has timing and level requirements. Without this tool, you would also need an oscilloscope for those measurements. I have not had any physical problems such as those shown in user photos (end caps coming off, for example.) The only complaint I gave is the labeling. The case is black plastic, and all of the legends and markings are just raised black-on-black lettering. (User photos here show white lettering, but mine looks like the primary product photo - just all black.) It makes things hard to read, especially for eyes that are more than six decades old. I know there are ways to make the letters more visible, but a brighter light was more convenient. I highly recommend this if you are working on desktop computer equipment. ### ⭐⭐⭐⭐⭐ Great for testing power supplies - even ones that appear "OK" *by A***N on January 4, 2013* This is wonderful for an instantaneous test of power supplies, to know if there is high or low voltage or a completely bad one. I work in a computer shop and have used this no less than 100 times for testing power supplies. There are a few cons of this product however to be aware of. 1. There isn't much documentation for instance it gives you a PG level, but no where does it tell you what this is. 2. The ends of the unit come off fairly easy where the plastic clips into the metal casing. It connects and tests 20/24 pin Motherboard connectors, 4 pin, and 8 pin EPS CPU connectors. SATA, Molex, and floppy connections, PCI-E 6 & 8 Pin connections. Good product overall with just the minor issues noted above. Would recommend to others. ### ⭐⭐⭐⭐ Needs instructions, but it does the job *by A***T on July 12, 2011* On the plus side, it works and gives you a good idea if your power supply is operating correctly or not. On the negative side, it beeps like a banshee if any of the voltages are out-of-whack. The beeping would be appropriate if this were a continuous tester, meant to be left in place while the system was in operation. In that case then, if a value went out of the normal range, then the beeping would be a plus. But for an intermediate tester like this one, where you're only going to be using it for a few minutes, the beeping is unbelievably annoying. (On that note: My dog thought it was the smoke alarm and totally freaked out over the sound.) Also, the instructions need help, but for that, see the rest of my review: INSTRUCTIONS: 1. First plug in the 20/24 pin motherboard power connector. 2. Hold the on button on the tester. All values except for +12V2 should be within their normal ranges (except possibly PG, see the end for details). 3. Don't unplug the 20/24 pin connector until you've tested everything else. 4. For each additional motherboard (4p/8p) or PCIE (6p/8p) connector, plug them in one at a time. When you hold the on button, the +12V2 should be in the normal range. Unplug each connector after you test it. 5. For each additional accessory (IDE/SATA/floppy) connector, plug them in one at a time. When you hold the on button, the +5 and +12 LEDs should light up. For most power supplies, the +3.3V LED should also light up for the SATA connector. Unplug each connector after you test it. NOTES: -All of the connectors with a clip (the 4, 6, 8, 20, and 24 pin connectors), plug in with the clip facing up. -The PG stands for "power good". This is the gray wire in the 20/24 pin connector. The power supply is supposed to do periodic self-tests and if everything is okay, then supply +5V along this wire. Some power supplies wire this directly to the +5V bus without doing the self-test. The tester detects this and will beep like crazy because of it. I have two known-good, high quality, name brand power supplies that "fail" for exactly this reason. -The SATA power connectors are supposed to supply +3.3V. However, in the early days of SATA, many people used IDE->SATA power adapters, but since the IDE power connector doesn't have +3.3V, neither did their SATA connector. As a result, very few devices actually use the +3.3V power and as a result, some power supplies might not supply +3.3V on the SATA connector (although they should). The point is that if you only get the +5V and +12V LEDs when you test your SATA cable, it's probably not a problem. -If the tester detects a very high or very low voltage, then it will flash "HH" or "LL". NORMAL RANGES (from the Coolmax website): Normal Voltage range Display Voltage range Line Ideal Lower (A) Higher (B) Min. (C) Max. (D) +5V 5.0V +4.75V +5.25V 4.0V 6.0V -12V -12V -11V -13V -10V -14V +12V1 12V 11V +13V 10V 14V +12V2 12V 11V +13V 10V 14V +3.3V 3.3V +3.14V +3.47V 2.0V 4.5V +5VSB 5V +4.75V +5.25V 4.0V 6.0V PG 0ms 990ms Unfortunately the tabulation isn't working right, but you should be able to work it out or find the original on Coolmax's website. So, for example, if you have 11.3V on the +12V2 line, then that is normal. If you have 10.5V, it is low and the tester will display "10.5". If you have 9.7V, it is low and the tester will display "LL". --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.gr/products/2855239-coolmax-lcd-power-supply-tester-ps-228](https://www.desertcart.gr/products/2855239-coolmax-lcd-power-supply-tester-ps-228) --- *Product available on Desertcart Greece* *Store origin: GR* *Last updated: 2026-08-14*