Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
Apr. 28, 2012	Apr. 30, 2011
Cash flows from operating activities:
Net loss	$ (10,399)	$ (14,180)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,139	2,872
Share-based compensation	2,872	1,680
Adjustments to provision for excess and obsolete inventory	381	1,046
Changes in operating assets and liabilities:
Accounts receivable	2,377	7,295
Inventories	1,701	(1,697)
Prepaids and other assets	158	(53)
Deferred revenue	(622)	(5,035)
Accounts payable	(867)	(1,838)
Accrued expenses and other current liabilities	(43)	(1,319)
Accrued restructuring costs	(294)	(78)
Net cash used in operating activities	(2,597)	(11,307)
Cash flows from investing activities:
Purchases of property and equipment	(1,303)	(1,796)
Purchases of investments	(257,891)	(410,001)
Proceeds from maturities and sales of investments	259,265	600,867
Net cash provided by investing activities	71	189,070
Cash flows from financing activities:
Payment of cash distribution to common stockholders		(185,446)
Proceeds from issuance of common stock	2,444	4,994
Net cash (used in) provided by financing activities	2,444	(180,452)
Net decrease in cash and cash equivalents	(82)	(2,689)
Cash and cash equivalents, beginning of period	60,765	104,416
Cash and cash equivalents, end of period	60,683	101,727
Cash paid for income taxes	$ 183	$ 91

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).