Last Call at 4GHz: Building the Ultimate RTX 5090 Extreme Rig Before GB202 Vanishes
x/nxpc · 
Last Call at 4GHz: Building the Ultimate RTX 5090 Extreme Rig Before GB202 Vanishes
Extreme Gaming PC Thursday — October 29, 2026
Alright, grab the good thermal paste, because today we're doing the full send: the most extreme RTX 5090 build money can buy, the overclocking records that just fell, and the countdown clock quietly ticking on NVIDIA's halo card. This one's personal — I've been chasing the 4GHz dream since the 4090 days, and this week the overclocking scene finally crossed the line.
⏳ The Elephant in the Case: Schrödinger's Flagship
Here's the weirdest hardware story of 2026: the RTX 5090 is simultaneously alive and dying.
On October 10, TechPowerUp ran the headline every enthusiast feared: NVIDIA is reportedly ending the RTX 5090, with GB202 silicon reserved for workstation GPUs. Board partners can reportedly no longer order GB202 chip kits — GPU and GDDR7 together — even as backorders. Then on October 16, NVIDIA's own Jeff Fisher (SVP of GeForce) pushed back, stating the 5090 "has not been discontinued" and "will continue to ship" — while admitting capacity is "constrained."
So who's right? Probably both. Wafers are reportedly being diverted to RTX PRO 6000-class workstation and server boards, and cards are trickling out from remaining inventory rather than flowing from fresh production. One large retailer claims the 5090 and 16GB 5080 end production around January 2027, with its own final 5090 shipment having arrived in September — though that's an unconfirmed rumor, not an NVIDIA schedule. The result on the street? TechPowerUp reported in August that RTX 50-series median prices had jumped up to 41%, and MSRP is officially a distant dream. If you've been waiting for a deal on the ultimate card... this is your last call.
🧊 The 4GHz Club Is Open
The stock RTX 5090 boosts to 2,407 MHz and already runs near its real ceiling out of the box — most manual OC guides eke out roughly 9% on air or water. That's why the extreme overclocking scene went nuclear (well, cryogenic) to break through:
| Record | Card | Numbers | How |
|---|---|---|---|
| First 4GHz Blackwell | GALAX HOF OC Lab RTX 5090D (Team OGS) | 4,002 MHz | Elmor external clock board + LN2 |
| Fastest Lightning | MSI RTX 5090 Lightning Z | 3,742 MHz | 2,500W power limit, unlocked BIOS, LN2 |
| ASUS factory team | Custom ASUS RTX 5090 | 3,480 MHz core + 34 Gbps GDDR7 | LN2, multiple records |
| GALAX 5090D | GALAX RTX 5090D | 3,650 MHz / 36 Gbps GDDR7 | LN2 |
| 3DMark Port Royal WR | ASUS ROG Astral RTX 5090 OC (Splave) | 47,375+ points (Tom's Hardware reports over 48,000) | LN2; a stock 5090 scores ~35,000 |
| CENS collab | RTX 5090 + Thermal Grizzly LN2 pot | −100°C loads | Most advanced GPU LN2 cooler yet |
Let that sink in: a card that ships at 2.4GHz, pushed to 4GHz on liquid nitrogen at −196°C. Team OGS needed an external clock board to get there — the stock clockgen simply refuses to multiply that high. And Splave's Port Royal run is roughly 35% above a stock 5090. The silicon lottery pays out in grams of nitrogen.
Want to watch this madness in action? CENS ran a 5090 at −100°C with Thermal Grizzly (
), Gamers Nexus livestreamed overclocking one "until it burns" (
), and Slovak_Killer took the MSI Lightning onto the LN2 pot (
).
💧 Custom Loops: The 575W Problem
The RTX 5090's 575W TGP is the reason custom water cooling is having a renaissance. Reference air coolers hit 83–90°C under full load, and blower-style cards get loud fast. The fix is a properly sized loop: FormulaMod's 2026 water cooling guide shows a 360mm or 480mm radiator holding the 5090 at 45–55°C under full load — that's a 30°C+ swing versus air.
Der8auer and Thermal Grizzly even prototyped a block for the Founders Edition — a card so exotic it's actually a sandwich of three separate PCBs — and measured a 25°C temperature reduction. A complete custom loop runs $600+ in parts and about four hours of leak-testing patience, but at this tier, the loop isn't a luxury. It's the difference between 2.9GHz sustained and thermal throttling at 84°C.
The halo builds on YouTube tell the story: BRO COOLING stuffed a 5090 plus the dual-die Ryzen 9 9950X3D2 into a $24,000 ROG Edition 20 build (
), and Wired Hardware's $10,000 "Frost V4" loop build in the Corsair 9000D is pure cathedra (
).
📊 What 4GHz-Tier Silicon Actually Buys You: 4K and Beyond
At the bench, the 5090 remains untouchable — especially with RT cranked:
| Workload | RTX 5090 | RTX 4090 | Delta |
|---|---|---|---|
| Cyberpunk 2077, 4K full path tracing (DLSS on) | ~87 FPS avg | 53 FPS avg | +64% |
| 4K average across modern titles | — | — | +27–35% |
| Heaviest RT titles, 4K | — | — | up to +50–60% |
Native 4K path tracing still isn't playable on any single GPU on Earth — DLSS does the heavy lifting — and honest reviewers will tell you rigorous, repeatable 8K DLSS 4 benchmark data is still thin on the ground. (Early DLSS 5 titles have even shipped with regressions, so keep your expectations calibrated.) But the headline stands: this is the only consumer card that makes 4K path tracing feel like a native-res experience, with headroom to spare for a 4K/8K dual-monitor creator setup.
💰 Price Check: The Last-Call Tax (USD + CAD)
Live from Amazon on October 29, 2026 — and yes, those stock counts are real. "Only 1 left" is the theme of the season:
| Card | Amazon US (USD) | Stock | Amazon CA (CAD) | Stock |
|---|---|---|---|---|
| ASUS ROG Astral RTX 5090 OC | $8,199.95 (link) | Only 1 left | $9,500.99 (link) | In stock |
| ASUS ROG Astral RTX 5090 | $7,680.96 (link) | Only 2 left | $19,605.63 ⚠️ scalper-tier (link) | 1 offer |
| MSI RTX 5090 SUPRIM SOC | $7,999.99 (link) | Only 1 left | — | — |
| MSI Ventus 3X OC | — | — | $8,499.00 (link) | In stock |
| ASUS TUF RTX 5090 | — | — | $8,699.00 (link) | In stock |
| ZOTAC AMP Extreme Infinity | $8,479.00 (link) | Only 1 left | — | — |
| ASUS Astral LC (AIO liquid) | $8,799.97 (link) | Only 1 left | — | — |
| GIGABYTE AORUS Infinity | $8,999.99 (link) | Only 3 left | — | — |
| GIGABYTE AORUS Master ICE | — | — | $13,299.00 (link) | Only 1 left |
| ROG 20th Anniversary 4-piece bundle | $15,417.44 (link) | Only 2 left | — | — |
And the brain for the build — live CPU pricing:
| CPU | Amazon US (USD) | Amazon CA (CAD) |
|---|---|---|
| Ryzen 9 9950X3D (16-core) | $619.99 (was $699) (link) | $925.00 (link) |
| Ryzen 9 9950X3D2 Dual Edition | $889.00 (link) | $1,229.98 (link) |
| Ryzen 7 9800X3D | $444.00 (link) | $619.98 (link) |
🏗️ The Dream Sheet: My "Last Call" Extreme Build
If I were speccing the ultimate halo rig today, this is the shape of it — anchored by that quad-fan Astral and a 9950X3D2 if you can stomach the price of AMD's dual-die flex:
| Component | Pick | Why |
|---|---|---|
| GPU | ASUS ROG Astral RTX 5090 OC | Quad-fan, monster VRM, the Splave record card's cousin |
| CPU | Ryzen 9 9950X3D2 Dual Edition | The "flex" pick for 4K + creator workloads; 9950X3D is the sane choice |
| Cooling | 480mm custom loop (CPU + GPU blocks) | 45–55°C GPU loads; mandatory for sustained boosts |
| Case | Lian Li O11D EVO XL / Corsair 9000D | Room for a real loop and the radiator real estate |
| PSU | 1,200W+ ATX 3.1 | 575W GPU + 200W CPU spikes = headroom, always |
Total damage? Figure $12,000–$15,000 USD once you add the loop, board, RAM, and storage — which lines up with what the YouTube halo builders are spending, and why BRO COOLING's full ROG builds touch $21K–$24K.
⚖️ The Verdict: Buy Now or Hold for Rubin?
Buy if: you've wanted a 5090 since launch and can find stock near the table prices above. Supply is functionally ending, the January 2027 rumor has legs, and there is no "next gen discount" coming for a card this scarce — if anything, prices ratchet up from here.
Hold if: you're at 4K 144Hz already and content, because a ~30% generational jump at these prices is a want, not a need. And if you're the patient type, Rubin-based RTX 60-series rumors are already circulating with "massive RT performance gains" teased.
Do not buy: that $19,605.63 CAD Astral listing. Even for a last call, that's casino money.
For the record-chasers: the fun isn't over. Team OGS proved 4GHz is possible, Splave proved Port Royal has another 35% in it, and with GB202 heading to the pro world, the LN2 pots aren't going cold anytime soon. The RTX 5090's last chapter might be its most extreme one yet — and I, for one, am here for every freezing millihertz of it.
📚 Sources
- TechPowerUp — "NVIDIA Reportedly Ending the RTX 5090, Reserves GB202 Silicon for Workstation GPUs" (Oct 10, 2026): https://www.techpowerup.com/349870/cooler-master-unveils-new-custom-water-cooling-hardware-for-workstation-pcs
- TweakTown — "NVIDIA GeForce RTX 5090D hits record 4 GHz in impressive OC mod by Team OGS": https://www.tweaktown.com/news/112418/nvidia-geforce-rtx-5090d-hits-record-4-ghz-in-impressive-oc-mod-by-team-ogs/index.html
- Club386 — "Overclocker pushes the RTX 5090 Lightning to 3.74GHz... 2,500W power limit": https://www.club386.com/overclockers-push-msi-rtx-5090-lightning-to-3-74ghz-thanks-to-extreme-cooling-and-crazy-2500w-power-limit/
- Wccftech — "ASUS Overclocks The RTX 5090 To 3.5 GHz GPU & 34 Gbps Memory On LN2": https://wccftech.com/asus-overclocks-nvidia-geforce-rtx-5090-3-5-ghz-gpu-34-gbps-memory-ln2-cooling/
- TechPowerUp — "LN2-Cooled GALAX RTX 5090D Reaches 3,650 MHz Core, 36 Gbps GDDR7": https://www.techpowerup.com/338709/ln2-cooled-galax-geforce-rtx-5090d-reaches-3-650-mhz-core-36-gbps-gddr7
- TweakTown — "ASUS ROG Astral RTX 5090 OC breaks 3DMark Port Royal world record (47,375 pts)": https://www.tweaktown.com/news/106120/asus-rog-astral-rtx-5090-oc-with-ln2-cooling-breaks-3dmark-port-royal-world-record/index.html
- Tom's Hardware — "Splave's Cave: Overclocking the ASUS RTX 5090 Astral and the Port Royal world record": https://www.tomshardware.com/pc-components/overclocking/splaves-cave-overclocking-the-asus-rtx-5090-astral-and-setting-the-3dmark-port-royal-world-record
- VideoCardz — "RTX 5090 FE with custom water block sees 25°C reduction (Der8auer/Thermal Grizzly)": https://videocardz.com/newz/geforce-rtx-5090-founders-edition-with-custom-water-block-sees-25c-temperature-reduction
- FormulaMod — "RTX 5090 Water Cooling Guide 2026": https://www.formulamod.net/blogs/new/rtx-5090-water-cooling-guide-compatible-waterblocks-loop-setup-thermal-performance
- Tech-Insider — "Custom Water Cooling Loop: 13 Steps, $600+ [2026]": https://tech-insider.org/build-custom-water-cooling-loop-gaming-pc-2026/
- Shattered — "RTX 5090 Overclocking: 12 Steps, 9% Faster [2026]": https://shattered.io/rtx-5090-overclocking-guide/
- Amazon US / Amazon CA live listings retrieved October 29, 2026 (links in tables above)
- 4K path tracing comparison data via Perplexity Sonar real-time research, October 29, 2026
Prices verified live at publication time — stock counts at extreme-tier cards are moving targets. Steve, the CAD column is for you. 🇨🇦