The recent rally in stocks screeched to a halt midday on Thursday with the major averages finishing well into the red. There were several Zacks #1 Rank (Strong Buy) stocks showing strong gains, however.

One such stock was Datalink Corporation (DTLK - Snapshot Report). Shares rose a stellar 8.9% on about twice its normal volume.

Datalink Corporation is an information storage architect for mid and large-size companies.

Earnings estimates have risen sharply since the company reported better than expected results for the second quarter of 2011, sending the stock to a Zacks #1 Rank (Strong Buy). Earnings per share for Q2 came in at 18 cents, crushing the Zacks Consensus Estimate of 11 cents.

It was the company's 4th consecutive positive earnings surprise.

Based on consensus estimates, analysts project 47% EPS growth in 2011 and 10% growth in 2012. Valuation looks reasonable with shares trading at 17x 2011 earnings, in-line with the industry average. Its PEG ratio is just 0.85 based on a 5-year EPS growth rate of 20%.

Spreadtrum Communications (SPRD - Snapshot Report) was another top performer from Thursday with shares up 8.6% on normal volume.

Spreadtrum is a fabless semiconductor company that manufactures baseband processor solutions for the wireless communications market. It is headquartered in Shanghai, China.

Earnings estimates have been surging since the company reported a 9% EPS beat for the second quarter. The 2011 Zacks Consensus Estimate has gone from $2.08 to $2.42 in the last 30 days, which corresponds with 78% growth over 2010 EPS. The 2012 consensus estimate has risen from $2.37 to $2.53 over the same period, representing 5% growth over 2011 EPS.

Shares trade at just 8x the 2011 consensus estimate, well below the industry average of 13x.

Other notable top performing Zacks #1 Rank stocks from Thursday include: MRV Engenharia e Participa (MRVNY), which was up 6.0%, Nautilus, Inc. (NLS - Snapshot Report), which rose 4.8%, and Heritage Commerce Corp (HTBK - Snapshot Report), which gained 4.7%.