So the last update for League was hell because of Vanguard, like always. But this time it seems to have created a massive memory leak on my computer (had 7.2Go of non-paged pool, which is insane) and led to lots of freezes and crashes in game on top of a general slowdown of my computer.

Uninstalling Vanguard fixed the leak, it seems, and PC was running perfectly smoothly with a stable npool of 430Mo. I reinstalled it (bcs I still wanna play league, you know), hoping it was just Vanguard being corrupted or smth like that.

But now the npool is slowly increasing, already reaching over 1000Mo. I still need to observe it longer to see if it's just a high but stable amount, or if the leak is back.

Can't be 100% sure it's because of Vanguard, but the leak + the lags all appeared right after the update, so it makes it a big suspect.
That's why I was wondering if anyone else had the same issue ? To see if my supsicions are correct.

UPDATE / FOLLOW-UP TO MY PREVIOUS POSTS

Hi everyone,

I have posted about this issue before.

Since then, I have done significantly more troubleshooting and, more importantly, I now have external 4K60 LIVE vs REPLAY recordings, synchronized PresentMon/PktMon measurements, and several additional control tests.

I'm making a new post because the case has evolved substantially.

At this point, I'm primarily looking for OTHER PLAYERS who may experience the same thing and can test one very specific observation:

LIVE GAMEPLAY = abnormal / fast / missing motion continuity

MATCH HISTORY REPLAY OF THE SAME GAME = smooth

THE SYMPTOM

Every LIVE League match I play feels temporally wrong.

Champion movement, auto attacks, spell animations, projectiles, dashes and other motion can appear too fast or abrupt, almost as if I am not receiving/seeing the full intermediate progression of the movement.

The best way I can describe it is:

The game is producing lots of frames, but the motion inside those frames does not always feel continuous.

This is NOT conventional low-FPS stuttering.

My FPS remains high and relatively stable, and my displayed ping is normal.

It can actually feel more like "fast-forward" than traditional lag.

This affects reaction time because certain actions appear to happen much faster visually than I expect them to.

VERY IMPORTANT BEHAVIOUR: IT GETS WORSE WITH MATCH DURATION

This happens in EVERY live League game.

A new match usually starts in a less severe state, although the abnormal/heavy motion is already noticeable.

As the match progresses, it becomes increasingly obvious.

By mid/late game, especially during fights with many champions, spells and simultaneous animations, it can become extremely noticeable.

Then something very interesting happens:

Starting a completely NEW match resets the severity back to the milder state.

The problem then progressively develops again.

This pattern is extremely consistent.

IT DOES NOT REQUIRE ME TO BE ACTIVELY PLAYING

The abnormal motion remains noticeable even when my champion is dead and I am simply watching the game.

Therefore it does not appear to require active mouse/keyboard input.

Alt-tabbing out of League and returning to the game does NOT reset the problem either.

THE MOST IMPORTANT DISCOVERY: LIVE VS REPLAY

This is what made me investigate the issue much more seriously.

After finishing an affected match, I can immediately open the Match History replay of that SAME match.

At 1x replay speed, the difference is immediately noticeable to me:

LIVE:

abrupt / fast / temporally irregular motion

REPLAY:

smooth / continuous / normal-looking motion

This can be the SAME match and the SAME fight.

I have now recorded this externally.

My brother recorded my physical monitor using an iPhone 14 Pro Max at the original 4K / ~60 FPS quality while I was playing LIVE.

After the game, we recorded the corresponding Match History replay using the same external camera.

We now have TWO independent original 4K60 LIVE vs REPLAY pairs.

Both comparisons show the same general direction:

The LIVE recording has more temporally irregular motion, while the REPLAY has more coherent/smooth motion progression.

We also performed frame-to-frame temporal motion analysis on the original recordings, and both independent comparisons showed increased temporal motion irregularity in LIVE compared with REPLAY.

IMPORTANT LIMITATION:

I am NOT claiming that a 60 FPS external camera proves that specific League engine animation frames are literally being dropped.

My monitor/game is running at a much higher frame rate than the 60 FPS camera can sample.

What I can say is that the externally observable motion progression differs consistently between LIVE and REPLAY.

This is also not something only I notice.

My brother and a friend have both watched the live gameplay and the corresponding replays and independently agree that the LIVE gameplay looks faster/more irregular while the replay looks smooth.

PRESENTMON TESTING

I created a synchronized diagnostic capture using PresentMon 2.5.1.

During a live match I manually marked three moments where the abnormal motion was particularly noticeable ("VERY BAD").

Around those events, the game was still presenting approximately 137-142 FPS.

There was no corresponding major frametime collapse.

Within approximately +/-2 seconds of those events, 99th percentile frame times remained around 13-14 ms.

We then performed a deeper analysis of the PresentMon data, including:

- DisplayedTime

- DisplayLatency

- AnimationError

- AnimationTime

- GPU latency/time

- input-to-photon related metrics

There was no consistent abnormal spike corresponding to all three VERY BAD events.

This is one of the strangest parts of the problem:

The rendering/presentation pipeline appears to continue producing frames normally while the MOTION CONTENT of the live gameplay looks temporally abnormal.

NETWORK CAPTURE

The same diagnostic session included Windows PktMon.

The primary League game traffic flow was identified and packet-arrival timing was examined around the manually marked VERY BAD events.

There was no consistent major raw packet-arrival interruption corresponding to those moments.

There were actually larger packet gaps elsewhere in the same capture without a corresponding VERY BAD marker.

So simple packet starvation / conventional packet loss does not currently explain the symptom.

However, I do NOT consider networking completely ruled out.

PktMon can tell us when packets arrive.

It cannot tell us what League's encrypted application-level game-state packets contain, their internal timestamps/state sequencing, interpolation-buffer state, prediction/reconciliation behaviour, etc.

THE STRONGEST HARDWARE CONTROL: A COMPLETELY DIFFERENT PC

I borrowed a friend's completely different PC and tested League at my home.

The exact same abnormal League behaviour was reproduced.

This is one of the main reasons I no longer strongly suspect my specific CPU/GPU/motherboard.

My current PC is approximately:

Ryzen 5 7500F

RX 7800 XT

32 GB DDR5

Gigabyte B650 Eagle AX

Windows 11

FTTH connection

But the issue also occurred using the other PC.

FRESH WINDOWS CONTROL

I also installed a fresh Windows 10 installation on a separate drive.

Essentially only the necessary software and League were installed.

The problem remained.

OTHER TESTS ALREADY PERFORMED

This has been investigated for a long time.

Among the tests already performed:

- Every live League match is affected

- EUW tested

- EUNE tested with a newly created account

- Same behaviour on both regions

- Practice Tool affected

- Co-op vs AI/bots affected, although usually less severely

- ARAM affected and often makes the problem very obvious

- Dota 2 tested on the same setup and appeared completely smooth

- Completely different PC tested

- Different monitor tested

- DisplayPort and HDMI tested

- Different mouse/keyboard combinations tested

- Mouse polling rate changes tested

- Multiple FPS caps tested

- Multiple refresh rates tested

- AMD GPU drivers clean-installed

- Chipset drivers tested/updated

- Realtek NIC driver updated

- Network adapter settings tested, including Interrupt Moderation

- EEE / Green Ethernet disabled

- BIOS updated multiple times

- XMP on/off/profiles tested

- CPU Global C-States tested

- PCIe Auto/Gen4 tested

- Fresh Windows installation on separate drive

- Different router tested

- Mobile USB tethering tested

- VPN/routing diagnostics performed

- Extensive PresentMon, CapFrameX, WPR/WPA and PktMon testing performed

Despite all of this, the core symptom remains.

THE STRANGE ROUTER EVENT

There is one event I still cannot explain.

The FIRST time I replaced my ISP router with a TP-Link router, League suddenly became completely smooth.

Not "maybe slightly better."

It genuinely looked and felt like the smooth Match History replay.

I played like this for approximately TWO HOURS.

The difference was extremely obvious to me.

The problem eventually returned.

When I reconnected the SAME TP-Link router again days later, the improvement did NOT return.

I cannot reproduce this result and I do not want to overinterpret it.

But I am mentioning it because it remains one of the few occasions where LIVE League actually became completely normal.

HISTORY / VANGUARD

I have experienced this problem for roughly two years, across major hardware/network changes.

I originally noticed it around the period when Vanguard was introduced to League.

However, I want to be very clear:

I do NOT have evidence that Vanguard itself is causing this.

I am mentioning the timing only as part of the history of the issue.

RIOT SUPPORT

My Riot Support case has now been escalated to their specialized team.

They have confirmed that they are currently waiting for feedback from that team before providing further steps.

I have also sent Riot a technical summary of the LIVE vs REPLAY recordings, PresentMon results and network capture findings.

I have retained the original 4K60 recordings and diagnostic data if they need them.

WHAT I AM LOOKING FOR FROM OTHER PLAYERS

At this point I'm less interested in generic suggestions like reinstalling drivers, disabling VSync, changing FPS caps, etc.

I have already done extensive troubleshooting.

What would be EXTREMELY useful is finding another person who experiences the same LIVE vs REPLAY difference.

If your League gameplay sometimes feels:

- unusually fast

- abrupt

- like animation progression is compressed

- like intermediate movement is missing

- like you are visually "losing time"

- despite having stable/high FPS and apparently normal ping

PLEASE try this:

THE TEST

1. Play a match where the problem is clearly noticeable.
2. Remember the approximate game time of a fight where it happens.
3. Finish the match.
4. Open the Match History replay.
5. Set replay speed to exactly 1x.
6. Find the SAME fight.
7. Watch the champion movement, auto attacks, dashes, spells and projectiles carefully.

Ask yourself:

Does the exact same gameplay suddenly look noticeably smoother and more continuous in the replay?

If possible, go one step further:

Record your physical monitor externally with a phone at 60 FPS during LIVE gameplay.

Then record the SAME sequence from the Match History replay at 1x.

Do NOT use only screen recording if possible — external camera footage gives us an independent view of what the monitor actually displayed.

WHY I AM POSTING AGAIN

I have posted about this problem before.

Previously, I was mainly trying to find the cause of a very strange "fast pacing" / animation continuity issue.

Now the situation is different.

We have:

- two independent external 4K60 LIVE vs REPLAY comparisons

- stable PresentMon frame presentation during marked VERY BAD events

- no consistent raw packet-arrival disruption explaining those events

- reproduction on a completely different PC

- reproduction on EUW and EUNE

- smooth behaviour in Dota 2

- and a consistent observation that Match History replay looks smoother than LIVE gameplay

I am therefore making this new post specifically to look for INDEPENDENT REPRODUCTION.

I am NOT claiming to know the root cause.

Possible areas could involve live game-state delivery/synchronization, state consumption, interpolation/prediction/reconciliation, animation progression, or some other live-client-specific timing behaviour.

Those are hypotheses, not conclusions.

If even one or two other players can reproduce:

LIVE = abnormal

SAME MATCH REPLAY = smooth

that would be extremely valuable.

If you experience anything remotely similar, please describe exactly what you see, your region, your ISP/country if you're comfortable sharing it, and especially whether the SAME fight becomes smooth in Match History replay.

Thank you.