UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-K/A

Amendment No. 1

For the year ended December 31, 2009

For the transition period from              to             

Commission File number 000-50687

ATEL Capital Equipment Fund X, LLC

(Exact name of registrant as specified in its charter)

600 California Street, 6th Floor, San Francisco, California 94108-2733

(Address of principal executive offices)

Registrant’s telephone number, including area code: (415) 989-8800

Securities registered pursuant to section 12(b) of the Act: None

Securities registered pursuant to section 12(g) of the Act: Limited Liability Company Units

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ¨    No  x

If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Act of 1934.    Yes  ¨    No  x

Indicate by a check mark whether the registrant (1) has filed all reports required to be filed by section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  ¨    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§229.405) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer. See definition of “accelerated filer and large accelerated filer” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes  ¨    No  x

State the aggregate market value of voting stock held by non-affiliates of the registrant: Not applicable

State the aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was sold, or the average bid and asked price of such common equity, as of a specified date within the past 60 days. (See definition of affiliate in Rule 12b-2 of the Exchange Act.) Not applicable

The number of Limited Liability Company Units outstanding as of February 28, 2010 was 13,971,486.

DOCUMENTS INCORPORATED BY REFERENCE

None.

EXPLANATORY NOTE

ATEL Capital Equipment Fund X, LLC (the “Company”) is filing this Amendment No. 1 to amend its Annual Report on Form 10-K for the year ended December 31, 2009, which was filed with the Securities and Exchange Commission on March 29, 2009 (the “Original Filing”). The Original Filing is amended to correct the number of Units outstanding as of February 28, 2010, as disclosed on the cover page, to 13,971,486 and to correct Exhibit 31.1, the Certification of the Chief Executive Officer.

Except as described above, no other changes have been made to the Original Filing. The Original Filing continues to speak as of the date of the Original Filing, and the Company has not updated the disclosures contained therein to reflect any events which occurred subsequent to the filing of the Original Filing, or to modify the disclosure contained in the Original Filing other than to reflect the changes described above.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: March 31, 2010

Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the persons in the capacities and on the dates indicated.

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