The 2020 TCL 6-Series R635 was the more ambitious TV, pairing mini-LED backlighting, quantum-dot color and Dolby Vision HDR with gaming features. The 4-Series S435 was a simpler, lower-cost 4K Roku TV. That makes the R635 the stronger feature set—not an automatic better buy today: its launch prices are historical, and current availability and value depend on the exact listing.
Which TCL models are being compared?
“4-Series” and “6-Series” cover multiple generations and variants. This comparison is specifically about the U.S. 2020 Roku TV models: the TCL 4-Series S435 and 6-Series R635. The S435 came in 43-, 50-, 55-, 65-, 75- and 85-inch versions, according to RTINGS’ S435 review. TCL announced the R635 in 55-, 65- and 75-inch sizes in 2020 (TCL’s launch announcement).
Check the full model number before comparing a listing. The S435 is the Roku version; RTINGS distinguishes it from the Android S434 and retailer variants S431 and S433. The R635 is an older generation, replaced by the R655 in 2022. Features announced for the R655 should not be assumed to apply to the R635 (RTINGS’ R635 review; TCL’s 2022 announcement).
How do the features and original prices compare?
| 2020 model | Picture and gaming features | U.S. launch pricing |
|---|---|---|
| TCL 4-Series S435 | 4K UHD Roku TV. RTINGS describes it as a basic, low-cost set that displays 4K content well and upscales lower-resolution content; it identifies slow response time and black smear as gaming drawbacks. | Not stated in the cited S435 review. |
| TCL 6-Series R635 | Mini-LED backlighting, up to 240 contrast-control zones, quantum-dot color, Dolby Vision HDR, VRR and Auto Game Mode, according to TCL’s 2020 announcement. RTINGS reports strong contrast and SDR brightness, a wide color gamut for HDR and VRR support, alongside picture and viewing-angle limitations. | 55-inch: $649.99; 65-inch: $899.99; 75-inch: $1,399.99. These were TCL’s U.S. starting prices announced August 11, 2020—not current prices. |
TCL’s mini-LED, zone-count and feature descriptions are manufacturer specifications, not independent proof of picture quality. RTINGS’ review provides a separate assessment of real-world strengths and drawbacks.
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- 4K UltraHD Resolution: Experience incredible detail with 4X the resolution of 1080p Full HDTVs
- QLED (Quantum Dot Technology): Rich, vibrant colors covering nearly the entire DCI-P3 color space to bring images to lifeQLED – Quantum Dot Technology: Rich, vibrant colors covering nearly the entire DCI-P3 color space to bring images to life
- 144Hz Panel Refresh Rate: Watch action-packed movies, fast-paced video games, and live sports with an ultra-smooth viewing experience, free of motion blur
- TCL AIPQ Pro Processor: Powerful, advanced processor that intelligently optimizes the color, contrast, and clarity for an unrivaled 4K HDR experience
- Dolby Atmos Audio: Advanced spatial audio processing can be found in movies, TV shows, and video games.
When does the R635 make more sense?
The R635 is the more capable choice on paper if you want HDR features, local dimming and gaming options beyond the S435’s basic setup. RTINGS found strong contrast and SDR brightness and a wide color gamut for HDR. TCL also included VRR and Auto Game Mode.
For gaming, note the input limitation: RTINGS says the R635 can run at 120Hz but lacks HDMI 2.1 bandwidth. The cited review describes the trade-off as 4K at 60Hz or up to 1440p at 120Hz. Check that against the resolution and refresh rate you actually need from a console or PC rather than treating “120Hz” alone as proof of 4K/120Hz support.
Rank #2
- 4K UltraHD Resolution: Experience incredible detail with 4X the resolution of 1080p Full HDTVs
- QLED (Quantum Dot Technology): Rich, vibrant colors covering nearly the entire DCI-P3 color space to bring images to lifeQLED – Quantum Dot Technology: Rich, vibrant colors covering nearly the entire DCI-P3 color space to bring images to life
- 120Hz Panel Refresh Rate: Watch action-packed movies, fast-paced video games, and live sports with an ultra-smooth viewing experience, free of motion blur
- TCL AIPQ Pro Processor: Powerful, advanced processor that intelligently optimizes the color, contrast, and clarity for an unrivaled 4K HDR experience
- Dolby Atmos Audio: Advanced spatial audio processing can be found in movies, TV shows, and video games
What are the R635’s drawbacks?
- Bright objects can bloom: RTINGS reports blooming around bright objects and rates the mini-LED local dimming as mediocre.
- Screen uniformity can vary: RTINGS notes uniformity issues.
- Seats off to the side see a weaker picture: the review describes a narrow viewing angle, making the R635 less suited to rooms where viewers sit well away from the center.
- 120Hz does not mean HDMI 2.1: the R635 lacks the bandwidth for 4K at 120Hz, as described above.
Who might prefer the S435?
The S435 may be the more sensible fit if you mainly watch shows and want a straightforward 4K Roku TV rather than paying for the R635’s more ambitious picture and gaming feature set. RTINGS calls it an okay low-cost TV and says it handles 4K content and lower-resolution upscaling, while identifying better gaming choices in its price range because of slow response and black smear.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.How to judge a listing today
The prices above are the R635’s 2020 U.S. launch prices; they do not establish what either model costs now or whether it is available. The R635 has been replaced, and current value cannot be inferred from its original MSRP. For any listing, compare the exact model and screen size, seller, condition and asking price, then weigh those against current alternatives and your room layout, content and input needs. The available model reviews and launch announcements do not establish 2026 stock, pricing or software-support status.
Quick Recap
Rank #4
- Real 4K HDR picture: A true 4K UHD (3840x2160) panel with Open HDR, HDR10, HDR10+, and HLG support delivers sharper detail and richer contrast than standard HD
- Built for gaming and sports: Game Accelerator 120 plus Auto Low Latency Mode (ALLM) and Motion Rate 240 with MEMC combine to cut input lag and smooth out fast motion, so this 65 inch smart TV keeps up with consoles and live sports alike
- Your next Roku TV: One simple home screen puts live local news, sports, movies, and thousands of free and paid streaming channels in one place — no separate streaming box required
- Works with your smart home: Compatible with Amazon Alexa, Google Home, and Apple HomeKit, plus built-in Google Cast and AirPlay 2 for mirroring video, music, and photos straight from your phone or laptop
- FullView bezel-less design: A slim metal, nearly edge-to-edge bezel keeps the focus on the screen for a clean, modern look as the anchor of your living room or home theater
Rank #3
- TCL QM6K QD-MINI LED TV SERIES - AFFORDABLE PREMIUM PERFORMANCE FOR SPORTS, GAMING & STREAMING. Experience superior contrast, rich color, and ultra-smooth motion with TCL’s QD-Mini LED technology. Designed to outperform traditional QLED and OLED TVs, the QM6K is the best TV for every moment—whether you're streaming, gaming, or watching the big game.
- QD-MINI LED. IT’S MINI LED PLUS QLED COLOR - BREATHTAKING BRIGHTNESS AND COLOR IN ANY LIGHT. Combines ultra-precise Mini LEDs with Quantum Dot technology for incredible brightness, bold contrast, and over a billion vibrant colors.
- TCL HALO CONTROL SYSTEM - BETTER BLACKS. SHARPER DETAIL. NO BLOOMING. Advanced local dimming eliminates haloing, enhances shadow detail, and improves picture accuracy—so dark scenes look deeper, and bright scenes stay crisp.
- DOLBY VISION, HDR10+, HDR10 & HLG - STUNNING HDR IN EVERY FORMAT. Enjoy 4K content the way it was meant to be seen. Dynamic HDR support delivers exceptional color, contrast, and detail across all major formats.
- 144HZ NATIVE REFRESH RATE + MOTION RATE 480 - SMOOTH, FAST ACTION—PERFECT FOR LIVE SPORTS. Watch fast-paced action with incredible clarity and minimal motion blur—making this one of the best TVs for sports.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
