* GameStop down 42%, AMC down 33%
* Silver tumbles from Monday's eight-year high
* Some Reddit participants say giving up on GME trade
* Robinhood raises $3.4 bln from investors in a week (Adds Musk, more comments from Reddit)
By Sagarika Jaisinghani and Thyagaraju Adinarayan
Feb 2 (Reuters) - GameStop shares sank on Tuesday and a silver buying spree led by small investors subsided as the Reddit-driven trading frenzy that has shocked global financial markets over the past week started to show signs of fizzling out.
The videogame chain's shares, which have see-sawed in a slugfest that has seen billions of dollars gained and lost by hedge funds and other financial investors, were down 42% at $130 in pre-market trading after scaling a high of $483 last week.
Spot silver prices, an alternative focus in the battle between a pack of small traders and Wall Street hedge funds, fell more than 5% after hitting an eight-year high a day earlier.
Analysts said the silver pullback may show the limits of small investors' impact in a large market, while posts on the popular Reddit forum, WallStreetBets, ranged from those giving up on the GameStop trade to calls to stick with the stock.
"The stocks side of things has faded because they all had a look at silver yesterday, but my feeling is they'll be back, depending on whether retail trading platforms will allow you to buy more than one share," said Keith Temperton, an equity sales trader at Forte Securities.
Another Reddit favorite, movie theater operator AMC, slumped 33% although it remains 500% higher than the start of the year, before the organized band of small buyers piled in and forced a "squeeze" that required big funds to close short positions by buying shares at very high prices.
Online broker Robinhood, on whose platform much of the buying and selling has taken place, confirmed on Monday it had raised another $2.4 billion from shareholders following a $1 billion boost last week as it strives to meet demands for additional collateral to cover trades.
The broker has also held talks with banks about raising another $1 billion in debt, people familiar with the matter told Reuters.
Analysts at financial institutions continued to predict the action, which has drawn the attention of regulators, politicians and celebrities, was likely to fade, it was just a question of how soon.
"The hope factor of this stock is very big," said Chris Bailey, strategist at Raymond James.
"So over this year, does the share price continue to go down? The answer is yes. We've seen it with internet shares in 2000 and so I think it will happen again."
In London, a sign of still-strong demand came from online greeting-card retailer Moonpig, which leapt 25% in its debut on Tuesday, while emerging markets research house Tellimer pointed to Ping An Insurance and Tencent as being ripe for a short squeeze in Asia.
Broader markets appeared to be moving on from the jitters the frenzied buying has triggered, and S&P 500 futures rose 0.8% on stimulus hopes.
Tesla Inc billionaire entrepreneur Elon Musk, whose candid tweets about certain companies helped send shares soaring last month, said he was taking another break from Twitter.
The number of shorted GameStop shares has fallen by more than half in a week, analytics firm S3 Partners said on Monday, although the videogame retailer remained the sixth-biggest short by value.
"There certainly exists a frothiness to this market that we are concerned about ... (but) we do think that this year has the potential to be a solid one for equities," said Joseph Amato, chief investment officer of equities at Neuberger Berman.
"Unlike these option-fueled stocks, valuations in general are underpinned by improving fundamentals."
One big drag on silver prices was an overnight margin hike on contracts for the metal by the Chicago Mercantile Exchange, which makes speculative trade using derivatives more expensive.
The U.S. iShares Silver Trust ETF, the largest silver-backed ETF, fell 5% before the trading bell a day after posting its biggest one-day gain in more than five months.
The ETF added about 20 million ounces of silver to its holdings on Monday following a record inflow of about 34 million ounces on Friday, taking its total to about 621 million ounces.
U.S.-listed mining stocks including First Majestic Silver and Pan American Silver also lost between 4% and 17%.
"It is slowing down a bit," said Gregor Gregersen, founder of Silver Bullion, a dealer in Singapore, after a wild 24 hours where he said sales exceeded average monthly levels from 2018 and orders above S$35,000 ($26,300) arrived every three minutes.
Hedge funds raised their bets against Canadian silver-mining stocks, January short-selling data from a market regulator showed.
Reddit moderators had on Tuesday removed one of the most popular posts suggesting buying silver and many WallStreetBets posts focused on riding out the volatility.
"WHO IS HOLDING GME WITH ME?" read one top post. "I'M HOLDING EVEN IF MY PORTFOLIO GOES DOWN TO ZERO," read another.
(Reporting by Thyagaraju Adinarayan in London and Sumita Layek, Swati Verma, Susan Mathew, Arpan Daniel Varghese and Shariq Khan in Bangalore; Writing by Tom Westbrook and Sagarika Jaisinghani; Editing by Jan Harvey and Bernard Orr)
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